Reverse/Back-up lights staying on while in Drive and when vehicle is turned off

[CobraKing]

Hey guys,

Noticed that on occasion the reverse/back-up lights stay on when in Drive or even when the vehicle is turned off. I have to turn the car on and then cycle through the gears until the lights go off. Did a little digging on the internet and it turns out some GMT900/NNBS trucks have an issue with the under-hood, fuse relay block going bad with exposure to the elements, crud, etc.. Could be the case as my truck saw duty in northern Ontario, Canada.

This is happening infrequently and I'd like to tackle it before it gets really bad and could potentially drain the battery as some others have experienced. They've had to replace the entire fuse relay block which costs several hundred dollars.

Just wondering if any of you have removed this block by chance? And if so how to go about doing it?

I took a quick look under the hood and the block has 2 grey handles that you pull together and pull up but at the same time there's about 3 or 4 connectors that appear to be plugged into it. My plan is to take it out and hit the contacts with some contact cleaner and a light wire brushing (after disconnecting the negative terminal on the battery).

Greatly appreciate any feedback and assistance. Thanks in advance!

 

[CobraKing]

Just posting a follow up here in case anyone else has the same issue. I was not able to remove the under fuse block completely as the harnesses (about 3 of them from what I saw) under the block would not disconnect when you pull on the 2 handles. There was also limited room to stick my hand in and disconnect said harnesses plus it's winter here in Ontario, Canada which reduces your overall garage work time.

However I did clean the fuse box completely with some automotive contact cleaner as well as remove and reinstall some fuses after spraying both male/female parts. The fuse block on my '14 truck was quite dirty despite only being about 3-4 years old. I recommend taking pictures of the fuse block before hand so that so that they go back in the right order.

Thankfully this cleaning helped as my reverse/back-up lights now stay off when the truck is turned off and while driving. A bit relieved as this part's about $350+ CDN and appears to be a bit of a headache to replace.

For anyone wondering, during the time it took me to clean the fuse box I had to pull out the fuse and drive with my reverse/back-up lights disabled as they were starting to stay on more frequently when turning the car off and also staying on even while driving.