[FIXED] Why is the Battery light on with key removed

2005 GMC 2500 6.0L. with the ignition key removed the battery light and shift indicator light come on and wont turn off. will kill the battery over night. I have a known good pars truck same make and model and swapped ignition switch and cluster and still have same issue. disconnected alternator and light stays on still. purchased new BCM and had it programed. still same issue. in researching the internet, seems this is a common problem but haven't seen anything confirming a fix. Any help would be greatly appreciated

is there any codes in any of the modules??

Any other symptoms? Along with scanning for codes like Cheryl mentioned, I'd be interested to know if there's any modules you can't communicate with.

I've seen failed engine grounds cause similar problems on other Chevy trucks, but they all had other problems (like not cranking, dash lights on while running).

from the looks of it on a wiring diagram the pcm controls the charge indicator and sends it over the serial data line to the cluster. lol since you have a parts truck swap the pcm and see if the light is on with the key off

did a code scan and there are no codes in any modules nd I can connect to all with no problems

yes I will swap PCM tomorrow morning.

swapped out the PCM this morning fixed the issue I had, thanks for all yall's input

you just gota get a new one and programmed... ouch... I figured the way the diagram looked it had to be the pcm. seeing that is controls the battery light

out of curiosity did the problem move to the other truck when switching the pcm??

cheryl hartkorn wrote: out of curiosity did the problem move to the other truck when switching the pcm??

Good questions here.

Slapping a [FIXED] on this one!