Okay guys.... I've been at this one for a while.
So I'll start here.
2002 GMC envoy
I've checked power from damn near everything I could think of and the grounds. Ignition switch, starter relay, fuel pump .. tons of my PCM wires to the fuse box as well (I had previously pulled the fuse box out and checked for good continuity) All mostly for the ignition and PCM connection wires.
This thing began as an intermittent no start. Sometimes it would, sometimes it wouldn't. Then it just didn't start
So, turn the key to run, dash lights are on, turn to start and it all goes black, no crank no sounds, nothing. Just dark.
Pulling the door unlock relay for whatever reason also can bring all of those lights on (sometimes no lights come on the dash) , and is how I had managed to get this vehicle started before.
I thought that it may have had something to do with the security system and getting locked out but am unsure. As there was a previous issue with the doors locking automatically. But the previous owner had just pulled the relay ( I believe it's the door lock relay)
I have been driving it for a week, no issues.
Today wouldn't start when trying to leave work. I pulled my good ol door unlock relay and got all my dash lights to come on, they weren't before. Tried to start it, and they go all black, like something is grounding out or the car doesn't think it's in park.
I went and pulled the starter relay, immediately put it back in and the car started and ran. (I've also got several of these relays I've interchanged before with no change)
However it wouldn't manually shift (it's an automatic) I had to shift it or it would drive around in 3rd gear no down or upshift. The blower motor didn't work which it normally does. And my ABS and 4wd service lights was on. Never was before.
I need some help figuring out what's causing this no crank no start issue please! Thank you for reading this...
So I'll start here.
2002 GMC envoy
I've checked power from damn near everything I could think of and the grounds. Ignition switch, starter relay, fuel pump .. tons of my PCM wires to the fuse box as well (I had previously pulled the fuse box out and checked for good continuity) All mostly for the ignition and PCM connection wires.
This thing began as an intermittent no start. Sometimes it would, sometimes it wouldn't. Then it just didn't start
So, turn the key to run, dash lights are on, turn to start and it all goes black, no crank no sounds, nothing. Just dark.
Pulling the door unlock relay for whatever reason also can bring all of those lights on (sometimes no lights come on the dash) , and is how I had managed to get this vehicle started before.
I thought that it may have had something to do with the security system and getting locked out but am unsure. As there was a previous issue with the doors locking automatically. But the previous owner had just pulled the relay ( I believe it's the door lock relay)
I have been driving it for a week, no issues.
Today wouldn't start when trying to leave work. I pulled my good ol door unlock relay and got all my dash lights to come on, they weren't before. Tried to start it, and they go all black, like something is grounding out or the car doesn't think it's in park.
I went and pulled the starter relay, immediately put it back in and the car started and ran. (I've also got several of these relays I've interchanged before with no change)
However it wouldn't manually shift (it's an automatic) I had to shift it or it would drive around in 3rd gear no down or upshift. The blower motor didn't work which it normally does. And my ABS and 4wd service lights was on. Never was before.
I need some help figuring out what's causing this no crank no start issue please! Thank you for reading this...
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