Help! My Tahoe won't shut off!

[angeleyez_2306]

Okay so I had my 07 Chevy Tahoe LTZ 5.3L washed and after I drove it home, the engine would not shut off. The ignition is in the off position and the key removed. Everything inside of the vehicle turns off like it would if the car was off, but the engine continues to run. You can't put the car into gear either when the ignition is in the off position. Unplugged the battery and the car still ran, had to pull the fuel pump fuse to get it to turn off. Was told it could be the ignition switch, replaced it and it's still doing the same thing. The car runs perfectly fine when the ignition is off, exactly the way it does when it's supposed to be on. I switched relays to see if one was bad, no change. Alternator was checked and it's fine also. The next day I tried to start it and it wouldn't start at all, the battery was completely dead. Charged it and it started but once again it wouldn't shut off. Something is draining the battery. I ended up taking it to a mechanic and he wants to charge me $900 to fix it. He said the engine fuse box is corroded (I checked it and there is no corrosion) and he said it needs a new total intergrated power module, I looked that up and it's only in Chrysler, dodge vehicles? Any advice would be greatly appreciated!

 

[iamdub]

I'm mostly lost on this one. About all I can say is that these cars don't continue running off the alternator when you disconnect the battery like the older cars did. So, whatever circuit needs to see the 12V from the battery is still getting it. I don't know what or where this circuit is or what components are part of it.

I'm sure you've already done this, but look wherever water may have entered the engine bay? Did they spray the engine when they washed it?

 

[angeleyez_2306]

I'm mostly lost on this one. About all I can say is that these cars don't continue running off the alternator when you disconnect the battery like the older cars did. So, whatever circuit needs to see the 12V from the battery is still getting it. I don't know what or where this circuit is or what components are part of it.

I'm sure you've already done this, but look wherever water may have entered the engine bay? Did they spray the engine when they washed it?

They didn't spray the engine bay, they did spray the undercarriage so I'm not sure if water went somewhere it wasn't supposed to or what. I've had multiple mechanics say they are lost on what is going with it.

 

[iamdub]

Well, it started after the spraying, so it's got to be related. Do you, or someone you know have a decent-sized air compressor? Get a blow gun (one with a long tip would be nice) and blow up from underneath. Have a bright light and blow around wire harness connectors, the PCM, underside of fuse/relay block, etc. Blow it in the same areas and manner that the water was sprayed. If you hit water that may be lodged inside a plug, blow all around until it's dry and see if the symptoms change.

 

[ISU-152]

Is it below freezing where you are? Maybe find a warm spot for it to sit/thaw and dry off first.

 

[angeleyez_2306]

Is it below freezing where you are? Maybe find a warm spot for it to sit/thaw and dry off first.

I live in Phoenix, AZ so far from below freezing.

 

[angeleyez_2306]

Well, it started after the spraying, so it's got to be related. Do you, or someone you know have a decent-sized air compressor? Get a blow gun (one with a long tip would be nice) and blow up from underneath. Have a bright light and blow around wire harness connectors, the PCM, underside of fuse/relay block, etc. Blow it in the same areas and manner that the water was sprayed. If you hit water that may be lodged inside a plug, blow all around until it's dry and see if the symptoms change.

I will try that! Thank you!

 

[2012LTZ]

i am having the exact same issue. can you tell me what you did to fix the problem?

 

[Chilo91]

Okay so I had my 07 Chevy Tahoe LTZ 5.3L washed and after I drove it home, the engine would not shut off. The ignition is in the off position and the key removed. Everything inside of the vehicle turns off like it would if the car was off, but the engine continues to run. You can't put the car into gear either when the ignition is in the off position. Unplugged the battery and the car still ran, had to pull the fuel pump fuse to get it to turn off. Was told it could be the ignition switch, replaced it and it's still doing the same thing. The car runs perfectly fine when the ignition is off, exactly the way it does when it's supposed to be on. I switched relays to see if one was bad, no change. Alternator was checked and it's fine also. The next day I tried to start it and it wouldn't start at all, the battery was completely dead. Charged it and it started but once again it wouldn't shut off. Something is draining the battery. I ended up taking it to a mechanic and he wants to charge me $900 to fix it. He said the engine fuse box is corroded (I checked it and there is no corrosion) and he said it needs a new total intergrated power module, I looked that up and it's only in Chrysler, dodge vehicles? Any advice would be greatly appreciated!

I’m having same issue can you let me know what you end up fixing?

 

[BCTahoe]

Same issue on a 2007 Tahoe. Anyone know the fix for this issue?
Thanks