Strange Electrical Problem

[bmacleod]

I have a 2002 GMC sierra 2WD. A while back the electric gear indicator in the dash went out but came back on shortly after. This happened a few times recently. I wasn't too alarmed until now. The selector now shows a different gear than the actual gear it is in. It varies all over the scale eg. it will sometimes showthat it is in reverse when it is actually in 3rd, neutral won't show, that kind of thing. I would suspect either something IP related or tranny related , except the door locks, which normally lock when you move and unlock again when you shut the truck off, now remain locked when you shut the truck off. If you turn the key forward again , the doors unlock. I can't draw a correlation between the 2 and I am thinking there may be a deeper problem somewhere . I have disconnected the battery to try and reset any computer which may cause an issue , but it had no effect. Has anyone ever had this issue or heard of a similar issue and could point me in a direction to start looking . Thanks in advance for any help and Merry XMAS.

[Bish]

The gear indicator light and the OD on my 01 also went dark and came back whenever it wanted to. I pulled the cluster and saw some cold solder joints. Hit them with a hot soldering iron and it solved the problem for over 100K until I got rid of it. That is an easy fix if you ave any electronics skills.

 

Don't know if it is related to the other strange things you are seeing but this is a pretty common problem with the clusters according to the speedo shop near me that works on them. Could be a combination of the shift selector module on the trans and a cold solder joint on the cluster.

 

Good luck!

[bmacleod]

Thanks bish, I was thinking that would be my next step and the soldering shouldn't be a problem. I determined later today that the door lock issue was because the selector would not show "PARK" or "P" , it won't trigger the locks to open, so it is related. I will look at the IP when the weather gets a little better. Thanks again.