Yesterday when I got home, turned off the key and the car kept running . Dash lights lite up , idle started surging . Turned key on and off it didn't help . Finally it stopped running . unhooked battery and reconnected . All the dash lights on without the key in it . Changed the rcm but it didn't help . No idea where to go from here .


this is with no key in it and in off position .

 

Do you have a remote starter fitted to the car as they have caused problems in the past.

 

no remote starter , would be nice to have one though .

 

I'm not sure exactly where you are in the process, so start from scratch and disconnect battery for a few minutes. While the battery is disconnected be sure the negative cable to the ground is good and clean; both the cable and the connection near the fender. Reconnect battery then try starting the car. What happens?
May actually have problem in the ignition switch/ key. Try contact cleaner?

 

Finally got a minute to test it more . Battery was disconnected all night , when hooked back up all the dash lights go on and it starts beeping all without the key in it .

checked all battery connections , all good .

When you turn the key nothing happens . Dash lights were already light up and truning the key does nothing to change it . see picture above .

Any ideas ? Dont know what to try next .

 

Your signature says you have a lightweight lithium battery, have you tried putting a regular battery back in the car?

 

1) ditto
2) can you pull any codes?
3) Are you sure the ignition switch is it self OK? Perhaps internals are shorted.
4) pull fuses: First open the small black box just forward of the larger box on the passenger side where the RCM, ECU and BCM are located. In that small box are three fusses that connect major components. Disconnect battery, then take two of them out. reconnect battery. Problem still there? No, disconnect battery and add one more fuse, reconnect battery. Problem there now? You are isolating problem to an area which will then be further explored. If the problem is isolated to the main fuse that powers the fuse box on the drivers side. Then start pulling fuses in the drivers side box to identify problem circuit.
4) Good Luck!

 

Seems like a stuck or shorted relay in the ignition circuit., low voltage will cause this as amperage rises with low voltage and welds contacts together, hence the lights staying on.... just a thought.

 

My guess would be that the contacts on the Engine Control relay are welded together.
Just a guess though.

 

I changed out the ecm and it made no difference . will try pulling fuses and rehooking up one at a time . My thought is the ignition switch . Are these known to go bad .

as far as the battery is concerned it is at 13.1v currently . Engine would have no way of knowing what type of battery it is . All the dash lights come on with no key .

 

You'd be surprised how finicky these cars are about battery and voltage levels.

 

I will try another . This battery has worked great for the last 2 years and just tested well . I have wanted to build a higher capacity one because the car sits for extended times so this is a good time to do it .

My wife is not a fan of my srt6 and has been pushing me hard to get one of the new 2020 mid engine Corvettes . But I like my SRT6 and put so little miles on it a year it makes no sense to buy a new car and rarely drive it . But I can here the " I told you so "coming from her soon .

 

New cars come with their own gremlins, like way too much electronics that ONLY a dealer can decipher. DON'T do it. These cars are so much easier to deal with, unless you lease and replace every three years.

 

RCM vice ecm?

 

King Happy, Read this thread, similar problem, car won't shut off