NEED HELP 2002 Chevy Trailblazer no crank

[BlueDazing]

So I am wondering if you are doing the relearn correctly and not writing your messages here right,,, or are you still NOT doing the relearn correctly.

You say here the "turned the key back to run". Do you not understand that you are supposed to turn the key to START?? Turning to RUN will NOT make the security light come on and stay on. The directions tell you to try to START the engine, not to just turn the key to RUN.

These procedures will never work unless the steps are followed EXACTLY as the directions say.

Actually I'm pretty sure I did turn it to start as an attempt to see if the truck suddenly fixed itself, but I don't remember that for certain.

What I do know is that if I go turn the key to start (the truck is off right now), the security light won't start blinking.

I could mess with the wire I soldered again just to get the security light to come back on but I'm not sure if this will result in any changes.

 

[BlueDazing]

This post was moved from another thread but is older than the posts already here. Please have a look.

So when I attempt to start the truck using the jumper switch, the security light does come on, and does not turn off after 10 minutes. Is this the scenario where I should leave it for an hour?

 

[BlueDazing]

hmmm .... are you sure it isn't "OL" as in "overload" which in resistance measurement is "infinity" (ie. high resistance).

I think we need to ensure what / how the meter works. What model is it?

I think you may be right, here is a picture of my meter with the option I had selected.

Those small letters/symbols on the bottom right of the screen are "kΩ".

 

[EXTeroceptor]

In an attempt to further narrow things down... have you checked out the wiring to your fuel pump at all?

I'm not sure how it's set up on a TB but usually it exits the body through a passthrough connector somewhere near the fuel tank and on to the evap and fuel components. I mention this because GM's of this era are notorious for issues related to the fuel pump wiring harnesses. It is located in a spot that is highly exposed to the elements. The connectors to the fuel tanks are also known to overheat, melt the plastic, cause shorts, etc. etc.

I had an '04 Grand Am that at one point started giving me starting issues. I beat on the fuel tank and it would start. For various reasons I was unable to replace it right away and since it would start with a few whacks I settled on doing that for a while. I actually fabricated a 'fuel tank beater extension device' so that I could beat on the fuel tank from the drivers seat while cranking the engine. Sometimes it would fire right up, sometimes it seemed like it was gone for good, but eventually would start. It did this about 1 in 3 starts. Then 1 in 4, 1 in 5, and eventually the problem went away. I ran on that same fuel pump for another year before I got rid of it and it was still going strong when I did. Just something to mull over...

It's possible that the wiring, or some connector involved, to the fuel pump isn't in such great shape and that even though enough juice can get through to prime, and thus start he engine, it quickly overheats with a constant current flow, raising resistance to the point where the fuel pump is not supplied with the current it needs.

When the engine dies after one second, is the security light on at that point? Or does it just die and then the dash looks like it does at KOEO? (key on, engine off)

When you do the relearn procedure that baker has suggested, after waiting 10 minutes and attempting the start the car, does the security light then turn back on? Or does it stay off? If it turns back on, (remember to attempt to start the engine, just hold it in start for the amount of time you normal would, then let the key sit in the on position for another 10 minutes). The security light should turn back on as you go to start the engine.

Here is an excellent video on the topic. It's for replacing a PCM, which you may or may not need to do, it's the additional information provided that will hopefully be useful

 

[BlueDazing]

In an attempt to further narrow things down... have you checked out the wiring to your fuel pump at all?

I'm not sure how it's set up on a TB but usually it exits the body through a passthrough connector somewhere near the fuel tank and on to the evap and fuel components. I mention this because GM's of this era are notorious for issues related to the fuel pump wiring harnesses. It is located in a spot that is highly exposed to the elements. The connectors to the fuel tanks are also known to overheat, melt the plastic, cause shorts, etc. etc.

I had an '04 Grand Am that at one point started giving me starting issues. I beat on the fuel tank and it would start. For various reasons I was unable to replace it right away and since it would start with a few whacks I settled on doing that for a while. I actually fabricated a 'fuel tank beater extension device' so that I could beat on the fuel tank from the drivers seat while cranking the engine. Sometimes it would fire right up, sometimes it seemed like it was gone for good, but eventually would start. It did this about 1 in 3 starts. Then 1 in 4, 1 in 5, and eventually the problem went away. I ran on that same fuel pump for another year before I got rid of it and it was still going strong when I did. Just something to mull over...

It's possible that the wiring, or some connector involved, to the fuel pump isn't in such great shape and that even though enough juice can get through to prime, and thus start he engine, it quickly overheats with a constant current flow, raising resistance to the point where the fuel pump is not supplied with the current it needs.

When the engine dies after one second, is the security light on at that point? Or does it just die and then the dash looks like it does at KOEO? (key on, engine off)

When you do the relearn procedure that baker has suggested, after waiting 10 minutes and attempting the start the car, does the security light then turn back on? Or does it stay off? If it turns back on, (remember to attempt to start the engine, just hold it in start for the amount of time you normal would, then let the key sit in the on position for another 10 minutes). The security light should turn back on as you go to start the engine.

Here is an excellent video on the topic. It's for replacing a PCM, which you may or may not need to do, it's the additional information provided that will hopefully be useful

The thing is, if there were something wrong with the fuel pump wiring harness, the key would most likely work still, but the engine would shut off after using it to start the engine.

I'm pretty sure that whatever is not allowing the key to start the engine, is the same problem causing the truck to shut off after a second, but I could be wrong and they could be two separate issues.

After the truck dies, the security light then comes on. It doesn't turn off after 10 minutes like it normally would during a proper security relearn. I left it for a good 25 minutes to see if it would eventually turn off and it just wasn't.

When I do the relearn process (which I am only able to do after disconnecting and reconnecting the yellow anti-theft wire under the ignition switch), it does not come back on after a single cycle. (As far as I remember.

 

[Mooseman]

I would try jumping the fuel pump relay to see if it keeps running running. And see if the PCM is the one killing the fuel pump or something else.

However, the security light coming on after starting seems highly suspect to me. You would need a scanner capable of seeing what the PCM and BCM are seeing for the security. It's weird that it doesn't have the security light on when first put to RUN however comes on after turning the key to START. Maybe the key lock cylinder sensor fails when it's turned to START.

Now if you totally wanted to eliminate the VATS system, you could send your PCM to be tuned to ignore VATS and start regardless. The light would still come on and flash but it would still start and run. http://www.lime-swap.com/ does this for $99 and can also do some other improvements at the same time.

But before spending the money on that, you have to be absolutely certain that your ignition switch is working correctly and outputting power to the wires as it should without interruptions (i.e. it doesn't cut power to the pink wire when it's turned to crank along with sending power to the yellow wire on crank).

 

[BlueDazing]

It's weird that it doesn't have the security light on when first put to RUN however comes on after turning the key to START. Maybe the key lock cylinder sensor fails when it's turned to START.

No, the security light does not come on when the key is in start, it will only come on if I jump the starter with the jumper switch.

How can I jump the fuel pump relay? And would that alone start the truck or would I need to jump the starter with the switch, and then jump the fuel pump within a second of it running? Like, is it a timing thing?

 

[budwich]

No, the security light does not come on when the key is in start, it will only come on if I jump the starter with the jumper switch.

How can I jump the fuel pump relay? And would that alone start the truck or would I need to jump the starter with the switch, and then jump the fuel pump within a second of it running? Like, is it a timing thing?

you have to jump both.... the fuel pump relay with not cause a start directly. You can temporally remove the fuel pump relay and run a jumper from one "switched" contact to the other "switched" contact in the socket.... make sure that you know which ones they are. The pump will start running but that won't be a problem just don't do this for long periods of time or with your tank empty. Once, you get the pump running, do your normal "workaround start" sequence. Your vehicle should run.

NOTE: it may not run longer because the theft operation may also cause a shutdown of the injectors.... depending on the system.

 

[budwich]

One more thing about your relearn sequence that people are questioning. You have to follow the sequence "exactly", INCLUDING doing the sequence "4 cycles" or until the vehicle starts as a result.... this follows the sequence posted by mooseman as few pages back. It is unclear to me that you have been doing that.

 

[BlueDazing]

you have to jump both.... the fuel pump relay with not cause a start directly. You can temporally remove the fuel pump relay and run a jumper from one "switched" contact to the other "switched" contact in the socket.... make sure that you know which ones they are. The pump will start running but that won't be a problem just don't do this for long periods of time or with your tank empty. Once, you get the pump running, do your normal "workaround start" sequence. Your vehicle should run.

NOTE: it may not run longer because the theft operation may also cause a shutdown of the injectors.... depending on the system.

If I do this and the truck continues run with it, what will that mean? And what would be the next step.

 

[budwich]

it means you are going to have one mighty funny looking fuse box...

I don't think it means much although it depends on the light status. IF there is no theft light, then it means that there is a fuel control issue (relay dropping). IF there is a theft light, it just means you found a way around it...

 

[BlueDazing]

it means you are going to have one mighty funny looking fuse box...

I don't think it means much although it depends on the light status. IF there is no theft light, then it means that there is a fuel control issue (relay dropping). IF there is a theft light, it just means you found a way around it...

So I attempted to jump the fuel pump relay and some changes have occurred.

I jumped from one switched socket to the other (87 to 30), it sparked when jumped, but attempting to start the truck only resulted in continuous cranking.

My dash lights are now showing a solid security, and some aren't even working properly such as the fuel tank reading empty (its not empty), and the gears/mileage are not showing up.

The BCM is quiet and does not sound like it is running anymore. (I could hear it humming before.)

My cheap scan too is refusing to read anything now, and is saying that it can't connect to the truck.

The truck doesn't even start now with the fuel pump relay back in place.

 

[mrrsm]

Take a Look at the the Cardone VTD Security Relearn Documentation after a Download & Save:

 

[budwich]

So I attempted to jump the fuel pump relay and some changes have occurred.

I jumped from one switched socket to the other (87 to 30), it sparked when jumped, but attempting to start the truck only resulted in continuous cranking.

My dash lights are now showing a solid security, and some aren't even working properly such as the fuel tank reading empty (its not empty), and the gears/mileage are not showing up.

The BCM is quiet and does not sound like it is running anymore. (I could hear it humming before.)

My cheap scan too is refusing to read anything now, and is saying that it can't connect to the truck.

The truck doesn't even start now with the fuel pump relay back in place.

:-( it does not sound good. IF the relay pin numbering was correct, you should have been providing power to the fuel pump. Did you actually here the pump turn on? check the pin on the relay with a meter... one set of pins should be the coil and the other set should be "fuel pump to nothing...ie no power" and the other should be continuity as the relay will switch away from that contact. I almost get the feeling you put power on the ground of the coil in the fuse box connectons.

 

[BlueDazing]

:-( it does not sound good. IF the relay pin numbering was correct, you should have been providing power to the fuel pump. Did you actually here the pump turn on? check the pin on the relay with a meter... one set of pins should be the coil and the other set should be "fuel pump to nothing...ie no power" and the other should be continuity as the relay will switch away from that contact. I almost get the feeling you put power on the ground of the coil in the fuse box connectons.

No, I didn't hear the pump turn on. The only thing that was noticeable was the spark when I jumped the 2 sockets.

When you say to check the pin with a meter, which pin are you referring to? The sparks did happen on a specific pin, the one I touched second with the jumper wire, so I can check that one if that is what you mean.

 

[mrrsm]

Did you Investigate the possibility of having any of the Fuses I Highlighted in RED on the Diagrams shown in Post #91 as having ***Burned Out*** since this event occurred?

 

[BlueDazing]

Did you Investigate the possibility of having any of the Fuses I Highlighted in RED on the Diagrams shown in Post #91 as having ***Burned Out*** since this event occurred?

Yes actually, fuse #10 for PCM B was burned out. I replaced it and heard the fuel pump activate (I think) and now the truck is back to the state it was in prior to breaking it with the fuse pump relay jump.

 

[BlueDazing]

Take a Look at the the Cardone VTD Security Relearn Documentation after a Download & Save:

Based on this PDF, I have the round key which says my truck uses passkey III.

It says my key has a transponder chip in it, and that leads me to ask, could the transponder chip in the key be broken?

I have 2 uncut keys with blank transponders that also have 2 blank key fobs that go with them, would i be able to use them?

Instead of having one of the keys cut, could I just cut the metal end of both my original key and the new one, and weld the fitting end of my original key to the transponder key base/handle of the new blank key?

Edit: Scrap that last part, I can actually get the key cut if it ends up being the problem.

 

[mrrsm]

Probably Not... Most Keys are either made of "Pot Metal" , VERY Mild Steel...or Chrome Plated Brass that will not tolerate the high temperatures needed for liquid metal bonding. You would be better off either ordering a Brand New $40.00 Lock AND Key Set like THIS from Amazon:

https://www.amazon.com/dp/B002E572IC/?tag=gmtnation-20

...Or... Take your Title & Registration to a Local GM Dealership and "Show The Paperwork" so they can sell one of these Over The Counter. It would mean carrying TWO Keys after that...One for the Doors and One Brand New Ignition Key (and Duplicate) like THIS... To "Put The Music" to the Ignition and get that Damned SUV to START & RUN...

You Know...The MORE This SAGA Plays Out... The MORE I would be inclined to run a CARFAX on this Vehicle and find out if it has any kind of "Sketchy Pedigree" with a Loan Jumper History in its Rear View Mirror... Whether Parked, Running...or Otherwise...

 

[BlueDazing]

Probably Not... Most Keys are either made of "Pot Metal" , VERY Mild Steel...or Chrome Plated Brass that will not tolerate the high temperatures needed for liquid metal bonding. You would be better off either ordering a Brand New $40.00 Lock AND Key Set like THIS from Amazon:

https://www.amazon.com/dp/B002E572IC/?tag=gmtnation-20

View attachment 107585View attachment 107584View attachment 107586

...Or... Take your Title & Registration to a Local GM Dealership and "Show The Paperwork" so they can sell one of these Over The Counter. It would mean carrying TWO Keys after that...One for the Doors and One Brand New Ignition Key (and Duplicate) like THIS... To "Put The Music" to the Ignition and get that Damned SUV to START & RUN...

You Know...The MORE This SAGA Plays Out... The MORE I would be inclined to run a CARFAX on this Vehicle and find out if it has any kind of "Sketchy Pedigree" with a Loan Jumper History in its Rear View Mirror... Whether Parked, Running...or Otherwise...

40 dollars is definitely manageable. But I'm confused, if I brought one of my blank keys to walmart and had it cut, would I not just be able to program it using the security relearn?

My theory was that if the transponder in the key is broke, the security light wouldn't come on because it doesn't recognize the wrong transponder, as there is no working transponder to be recognized in the first place (if its broke.) And since the key is not recognized, the truck will not stay running when I start it with the jumper switch.

And I don't think I have a local GM Dealership anywhere near where I live, at least not within an hour drive.

 

[mrrsm]

Look... I've suspected that "Something has been A-MISS" inside of the Lock-Work in your Key Tumbler all along. Everything that shunts the VATS in your Steering Column begins and ends with "The Turn of A Key"...and if that internal mechanism is damaged inside or perhaps, just plain worn out... It would NOT hurt to replace the Whole Damned Thing. Then just follow the Instructions mentioned in the Cardone VTD PDF to re-set or re-train the Security System.

And if I'm right ...and THIS is what it takes to sort everything out... it would be Money Well Spent and really Very LITTLE inconvenience with having to carry Two Different Keys to get inside the Locked Door with One and then use the Other to Start The Engine.,. Keeping it Running and .then.. Just Drive On... :>)

 

[Mooseman]

actually, fuse #10 for PCM B was burned out.

More than likely, it blew from being jumped incorrectly.

AFAIK, all GMT360/370 use PassLock with no chip or transponder in the key. The only exceptions are the Saab 9-7x and exports out of North America. Look for PK III engraved on the key shaft. That picture of the different keys is incorrect as you can have PassLock keys with the rounded plastic covering.

 

[budwich]

No, I didn't hear the pump turn on. The only thing that was noticeable was the spark when I jumped the 2 sockets.

When you say to check the pin with a meter, which pin are you referring to? The sparks did happen on a specific pin, the one I touched second with the jumper wire, so I can check that one if that is what you mean.

you should confirm all the pins at the connector by looking at schematic. There is two pin of concern... one that is a ground for the relay coil....only bad things will happen f you put battery on that one. The other is a path to the fuel pump... this is the one that jump battery two. The pump should run continuously. It may spark a bit as it is a motor winding. Measuring the resistance on the pin (to ground) will tell you how low it is... may guess about 2-3 ohm which means you will see 4-5 amp which is a pretty good spark.

 

[mrrsm]

On the"Class 2 Network" side of this issue... Paul "Scanner" Danner's Main Page has an SD member there who got into trouble with his 2004 Trailblazer when some of the Network wiring to the BCM got cut loose near the Center Console area and then got "Tangled Up" during a misbegotten repair.

The Value of this Link is that he provided a pair of images of the Class 2 Network Wiring that displays the "Immobilizer" circuit and its relationship to the BCM in plain view ...and it certainly won't hurt to learn more from his discussion about the how the "Immobilizer" works:

2004 Trailblazer fixing an issue caused by an idiot

2004 Trailblazer fixing an issue caused by an idiot

www.scannerdanner.com

I'm still curious about how the Four Wire Plug-In Harness works that hooks into the Ignition Switch and the Key Tumbler Lock Work area and whether or not IT might still be involved if anything was either cut or damaged therein. Here are some images highlighting that location along with an Exploded Schematic of the whole mess:

Take a look at THIS interesting "THING" that is Taped into the Wire Harness Under the Steering Column. It turned out to be a Wirelss GPS Tracker Unit wired into an SUV that was under lien and it acted to both Locate and Disable the Vehicle if payments did not arrive on schedule.

It might be worth "Unbolting" that Metal Knee Bolster Shield on the Lower Dash area and then access the Ignition Harness down there. Then locate the Wire Harness attachment block (Small Translucent Red Painted Fastener) at the base of the steering column and after unbolting it... pull it loose and make a very close examination of all that stuff with a "Graduated Eye Ball":




Oh... I Forgot to mention this back in Post #9... But in the normal sequence of events... IF your get ANY Interruption of the IGN1 Circuit OR LOSE THE IGNITION SWITCH at any time during Start-Run... You SHOULD be seeing a "PASS-LOCK" Security Warning Light show up on the Dashboard and it SHOULD Remain "ON" afterwards. If there is a Switch Input Signal (Like a Power Mode Input) that was being incorrectly displayed from the BCM back to the PCM ...that "PASS-LOCK" Light would Activate immediately... and remain LIT.

 

[Mattb.]

I had same issue with an 08’ i had, it would start through the relay, but like you said only for a second, it only sat for maybe a month if that, all lights worked inside and out , windows , power locks, wipers, headlights , radio, the radio would cut out when key was turned, then it would play again, the only light i did not see ever come on was the security light, i was told i would have to bring it to a chevy dealer, have them flash it, it was a 50/50 it might work. i had so many good parts on the truck, tires brakes, rotors, engine was string, 4x4 worked great, sooo disappointing! I sold it for parts!!

 

[mrrsm]

I've been Thinking about suggesting something a "Bit Crazy" since We have not dwelt upon the issue of GROUNDS very much. But ... if THIS "Thing" Works... it might just get to the bottom of this problem much sooner than later. THIS is the Idea:

(1) Purchase THIS New Starter Relay (as a Back Up):



(2) Then... Use your Old OEM Starter Relay and simply SOLDER ON A GROUND WIRE TO PIN 85 near the Upper portion where the Tine meets the underside of the Plastic Relay Casement:



(3) Now... SOLDER on an Eyelet at the opposite end of the Ground Wire and then Fasten it to an adjacent Clean, Smooth Metal surface area of the Body-Chassis.

(4) Carefully insert the Modified Starter Relay and then Attempt to Start and RUN The Engine...

(5) ANY Sketchy Ground Copper Traces in the Under Fuse Block can thus ...be side-stepped.

 

[BlueDazing]

Hey everyone, I know this is an old thread but I'm now in a better position to get this truck running and wanted to give it another go. I have a job now, as well as a car. My daily driver is a 2009 Chevy Impala LS, and it's a really nice car.

I can afford to buy a scanner, and I still want to get the truck running so that my brother can use it. As far as I remember, the truck has an issue with either the PCM, BCM, or ignition switch.

I don't want to have to spend 200 dollars on a tech II scanner, do any of you know a scanner I can buy for a reasonable price, that will give me PCM or BCM error codes?

 

[Mooseman]

Sure. The Veepeak bluetooth ELM327 adapter:

https://www.amazon.com/dp/B011NSX27A/?tag=gmtnation-20

There's the Chevrosys and Car Gauge Pro apps that can scan everything. @TJBaker57 can also show how to do it with command lines with a free app.

 

[TJBaker57]

Hey everyone, I know this is an old thread but I'm now in a better position to get this truck running and wanted to give it another go. I have a job now, as well as a car. My daily driver is a 2009 Chevy Impala LS, and it's a really nice car.

I can afford to buy a scanner, and I still want to get the truck running so that my brother can use it. As far as I remember, the truck has an issue with either the PCM, BCM, or ignition switch.

I don't want to have to spend 200 dollars on a tech II scanner, do any of you know a scanner I can buy for a reasonable price, that will give me PCM or BCM error codes?

Are you an iPhone user or Android?

The Veepeak Mini Bluetooth adapter that @Mooseman linked to is a reliable very low cost adapter that will work with a number of phone apps. I have 4 or 5 of these adapters and this manufacturer/model has never failed me.

This is worth bringing up, the adapter is only a communications gateway to the vehicle network. Hardware only, it does not "do" anything for you by itself. Some form of software is required.

As for software to use there is an abundance of phone apps available. Torque Pro is the undisputed leader in market share here and is Android only, no iPhone version exists. The free "lite" version is quite limited so it is strongly advised to purchase the Pro version. (Under $10)

Even the apps need further enhancements to be entered by the user to customize for the vehicle(s) you are working on. That is where we come in. We can provide add-on enhancements (free) and guide you in what to add in and how to add it.

As good as Torque Pro is there are weak spots where other apps can outperform Torque Pro. Car Scanner ELM OBD2 is one such application. OBD Fusion is another and OBD Fusion does have an iPhone version also. Each has their strong and weak spots. Most users at least start out with Torque Pro.



Another somewhat more expensive option that can read about anything a Tech 2 reads is the Autel Maxi AP200 available from JBTools.com for about $35 plus shipping. (Not the later models like 200M etc which I believe are subscription based, but the original AP200).

Autel MaxiAP OBD2 Scanner Bluetooth Diagnostic Tool (AP200)

Connect and diagnose your vehicle efficiently with the Autel MaxiAP (AP200), a Bluetooth-enabled OBD2 scanner.

www.jbtools.com

Some bullet points;

(1) The application takes a lot of phone storage. On my samsung the app uses a little more than 1 Gigabyte of storage space.

(2) You register this device with an email address and the device is then 'linked' to that email and your acount. Included with the purchase price you get ONE manufacturer line for lifetime use, not a subscription. This gets you the ability to use the device with any number of vehicles from that manufacturer. I have one device I registered for GM and another I registered for Ford (my girlfriend has a 2008 Ranger). I have 2 more devices that I have not yet registered.

(3) The device reads pretty much everything (live data) a Tech 2 reads but this does NO PROGRAMMING, and the special functions are limited at best.

(4) This device does not get you the ability to record data and is not a convenient opion for monitoring data as you drive. It is best suited to diagnostics.

 

[BlueDazing]

Are you an iPhone user or Android?

The Veepeak Mini Bluetooth adapter that @Mooseman linked to is a reliable very low cost adapter that will work with a number of phone apps. I have 4 or 5 of these adapters and this manufacturer/model has never failed me.

This is worth bringing up, the adapter is only a communications gateway to the vehicle network. Hardware only, it does not "do" anything for you by itself. Some form of software is required.

As for software to use there is an abundance of phone apps available. Torque Pro is the undisputed leader in market share here and is Android only, no iPhone version exists. The free "lite" version is quite limited so it is strongly advised to purchase the Pro version. (Under $10)

Even the apps need further enhancements to be entered by the user to customize for the vehicle(s) you are working on. That is where we come in. We can provide add-on enhancements (free) and guide you in what to add in and how to add it.

As good as Torque Pro is there are weak spots where other apps can outperform Torque Pro. Car Scanner ELM OBD2 is one such application. OBD Fusion is another and OBD Fusion does have an iPhone version also. Each has their strong and weak spots. Most users at least start out with Torque Pro.



Another somewhat more expensive option that can read about anything a Tech 2 reads is the Autel Maxi AP200 available from JBTools.com for about $35 plus shipping. (Not the later models like 200M etc which I believe are subscription based, but the original AP200).

Autel MaxiAP OBD2 Scanner Bluetooth Diagnostic Tool (AP200)

Connect and diagnose your vehicle efficiently with the Autel MaxiAP (AP200), a Bluetooth-enabled OBD2 scanner.

www.jbtools.com

Some bullet points;

(1) The application takes a lot of phone storage. On my samsung the app uses a little more than 1 Gigabyte of storage space.

(2) You register this device with an email address and the device is then 'linked' to that email and your acount. Included with the purchase price you get ONE manufacturer line for lifetime use, not a subscription. This gets you the ability to use the device with any number of vehicles from that manufacturer. I have one device I registered for GM and another I registered for Ford (my girlfriend has a 2008 Ranger). I have 2 more devices that I have not yet registered.

(3) The device reads pretty much everything (live data) a Tech 2 reads but this does NO PROGRAMMING, and the special functions are limited at best.

(4) This device does not get you the ability to record data and is not a convenient opion for monitoring data as you drive. It is best suited to diagnostics.

Alright, so I got the scanner that Mooseman linked, and downloaded Car Scanner ELM from the android playstore. When I put the key to run, plugged in the scanner and connected it to my phone, I scanned for codes and read 0. I attempted to run the truck by jumping the relay, it started, and after a second shut off. I still read no codes. I then set the app to read "All command sets + common non-standard addresses + extended diagnostic command" and it output 38 error codes. All of them were "pending not tested". I'm not sure if this was accurate or not but I tried as much as I could within my understanding, and now I need assistance again.

 

[TJBaker57]

I need to go back and reread the thread to see what the issue was! I will edit this post soon when I am caught up.

OK, this thread has a lot of traffic and much has transpired.

Some questions for you: What is the status of the truck today? Does it still crank? Does the engine still start and run for a second or two? What does the security light do? That sort of thing, just update us on the current status.

I am fairly sure I can set you up with some additional data points to add into Car Scanner that will let us see what the Passlock Security System is seeing/doing.

I need more coffee first though!

 

[BlueDazing]

I need to go back and reread the thread to see what the issue was! I will edit this post soon when I am caught up.

OK, this thread has a lot of traffic and much has transpired.

Some questions for you: What is the status of the truck today? Does it still crank? Does the engine still start and run for a second or two? What does the security light do? That sort of thing, just update us on the current status.

I am fairly sure I can set you up with some additional data points to add into Car Scanner that will let us see what the Passlock Security System is seeing/doing.

I need more coffee first though!

The truck is in the same condition as it was when I stopped responding. When I turn the key, all of the dash lights come on, but no security light. The car does nothing when I crank the key—no click noise, just silence. When I start the truck through the starter relay in the fuse panel, it cranks, starts, runs for a second, and shuts off. I think at this point the security light comes on, but I would have to check again, as I didn't check for that when I started it earlier this morning.

 

[TJBaker57]

When I turn the key, all of the dash lights come on, but no security light. The car does nothing when I crank the key—no click noise, just silence.

So your security light does NOT turn on, then turn off during the "bulb check" part of the startup sequence as seen in this video at the 15 to 19 second mark ??

And the security light does not come on after turning the key to crank and letting the key come back to the run position?

 

[BlueDazing]

So your security light does NOT turn on, then turn off during the "bulb check" part of the startup sequence as seen in this video at the 15 to 19 second mark ??

And the security light does not come on after turning the key to crank and letting the key come back to the run position?

It turns on during the bulb check, but turns off with the rest of the lights that don't normally stay on.

And no, it does not come on after cranking and returning to run.

 

[mrrsm]

The Admin(s) or Mod(s) might consider making a *Sticky* of Tom's Video ( @TJBaker57) in Post #153 into the FAQ Thread. Very Nicely Done.

 

[BlueDazing]

I am fairly sure I can set you up with some additional data points to add into Car Scanner that will let us see what the Passlock Security System is seeing/doing.

I would still like to see if we could find anything using this scanner, any ideas?

Whoops, this was meant to be a reply to your comment, @TJBaker57.

 

[BlueDazing]

Hey guys, I haven't heard from any of you in a while. I'd still like to try and get this truck running, any ideas with the scanner?

 

[mrrsm]

Give THIS approach a try...

(1) Pull the Fuse Box Cover(s) and unscrew the Three 7mm Galvanized Studs.
(2) Reach underneath and pull loose the related Plastic Fuse Block Harnesses.
(3) Spray out EVERYTHING... Inside & Out with CRC Electrical Contact Spray.
(4) Allow all of these Assemblies to DRY and plug them back in and Tighten the Fasteners.

 

[TJBaker57]

Hey guys, I haven't heard from any of you in a while. I'd still like to try and get this truck running, any ideas with the scanner?

Did we ever verify the circuit path from the ignition switch yellow wire through the associated harnesses etc. to the PCM? This can be checked by reading the resistance from the yellow wire to a known good ground. Red test lead to yellow wire, black test lead to chassis/frame ground. It can be tested with the key in any position EXCEPT "Start". It should read about 1200 ohms.

When we think about what happens when the key is turned to the "start" position we usually just test for voltage at the yellow wire. But this doesn't prove the voltage is getting to the other end at the PCM.

My own 2002 Trailblazer has a poor connection at the crank fuse to fuseblock junction.