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ENGINE CRANKS UP WITHOUT KEY WHILE CONNECTING BATTERY!

tjc82

New Member
Joined
Jul 13, 2007
Messages
3
Location
West Monroe,LA
? ?I'm new to this forum but hope someone can help me with a perplexing problem with my '03 Z66 Ava.
? ? I had to remove my battery to do some fender repair. After making the repair I reinstalled the battery. I connected the positive cable first and upon connecting the ground cable the engine started up.The ignition was turned off and the key wasn't in it. The dash was lit up like a Christmas tree the lights were on and the buzzers were buzzing.
? ? I placed the key in the ignition and turned it on and then back off but it continued to run. I managed to kill it by removing the PCM fuse.
? ? After replacing the fuse I turned the key and it stated up normally and idled right. I turned it off and didn't test drive it.
? ? ?The next day I had to once again disconnect the battery and in the process of hooking it back up it once again started up without the key. I repeated the process of removing the PCM fuse to kill it.
? ? ?I once again put the key in and it cranked up and was idling fine but it read "reduced engine speed" the tracking control light was on and would not turn off and the accelerator would not respond.? I checked for a code and it showed "P1125" in reference to the TAC. It has now started to die after idling for about a minute.
? ? ?I have looked to see if the wire harness was tight under the underhood fuse panel. beside the battery. It was tight.
? ? ?I know by the code that the PCM is not receiving the correct info from the TAC. My thinking is to replace the Accelerator Assembly since the sensors can't be replaced individually.
? ? My? dilemma is will that cure the problem or is possible the PCM is bad?
? ? Hope someone can help as I suspect this could expensive real quick.
 
:welcome:Sorry I cant help with your problem but I am sure someone will be along shortly. Good luck
 
welcome to the club tjc82

most of the references to that code setting on here are in regards to driving through a big puddle, but it sounds like you are on the right track

found some additional info on that code here
 
Definitely not moisture as it has been inside a closed garage for a month. Thinking when I installed the battery I may have loosened one of the connections that go to the fuse panel beside the battery but I can't seem to find any. Maybe I shorted something?
 
Ignition switch inside?

or do yo have remote start system?
 
? ?I have found the problem with the accelerator. It was a loose wire harness on the firewall at what I assume is the TAC. It is the between the brake master cylinder and fender well. I don't recall working on that area when working on the fender but I must have. As for the starting up when hooking up the battery I havenot tried it again. Kind of reluctant to do so, afraid I might short something out. It doesn't have a remote start switch that I'm aware of. I bought the Ava used and so I don't know what the previous owner may have installed. The only alteration from stock that I know of is the accelerator height pedal adjustment has been disconnected. Don't know why.
 
Wondering if anyone else has an idea on this since it's been awhile. Today my 03 z71 did the same thing. Connected the battery, a few clicks from the fuse block then the truck started. Keys were on the ground next to where I was working. I disconnected the battery, waited a minute then reconnected. Same results, clicking and starting. It would only run for 3 seconds then shut off. Finally connected battery, started with the key and drove it. Everything seemed to be working fine. I swear this thing is Possessed! Christine 2.0.  :eek:
 
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