2009 Silverado No Backup Lights

ChevMech · October 31, 2017

Okay guys, It's been a long time since I've posted, but I'm having a little bit of a problem. My 2009 2500HD gas has no back-up light. None, nada, zip....nothing. I have run a hot wire to the fuse and they light up, so i know the wiring to the back and the bulbs and sockets are working. They don't, however, turn on when you put the truck into reverse, or when the rest of the perimeter lighting is engaged. I also have nothing on the trailer circuit.

Besides running that jumper wire, I have done nothing but check the fuses, and despite what the google machine says, there is no relay on this one. Is there a common failure on these trucks that would cause this problem?

Formulabruce · October 31, 2017

Ok , Underhood in the big Fuse box power block there should be a few marked for trailer lights. I am thinking one of these fuses is blown. Also could have a switch on the Transmission that is bad.. Good luck!

ChevMech · October 31, 2017

This is going to be my project for this weekend, so I'm going to take a tester to everything that may or may not be related to the backup light circuit.

My next question, where is the back-up light switch located on the transmission? I'm not seeing a switch designed for this function on any parts websites. A Google search shows two thing: either one that threads in, or the neutral safety switch.

SpartanAutoworx · November 10, 2017

could be a bad bcm

davester · November 11, 2017

check all the fuses, both in the underhood fusebox and the one in the drivers end of the dash. I've had another, unrelated fuse blow (but offhand, I don't recall the specific one) because of a wiring problem, and that resulted in the backup lights not working.

citydriver · November 13, 2017

There is a relay, but it's not serviceable, it's a PCB relay mounted to the board inside the under hood fuse block that is triggered by the BCM after it receives a signal from the transmission control module. But I would check the fuse and the fuse socket / connections. I have been noticing some corrosion on my under hood fuse block connections lately. On both sides, the top you can see and the underside that you can't see. I basically removed the under hood fuse block to clean and inspect ALL of the connections for the fuses, relays and harness connectors under the block, then used a plastic bristled brush and applied a thin coat of di electric grease to all of the contacts. I did this as a preventative measure to help keep the corrosion from getting out of control. Hopefully that's all you will find is a dirty connection. Otherwise you will need a Tech2 or similar to check the signals from the modules.

ChevMech · November 22, 2017

So let’s say it is the relay, what’s the next step?

Edited November 22, 2017 by ChevMech

ChevMech · December 8, 2017

Just a quick update: I found the problem with my faulty reverse lights: the relay under the fuse panel is blown. I borrowed the fuse panel out of my parents' Tahoe and everything worked as it should.

While I was looking for a replacement (let me know if you have one) I found that this is a really really really common problem on GM trucks of this generation. I read that the ground strap from the firewall to the engine cracks/breaks causing power surges of sorts. The most obvious of symptoms: the relay for the backup lights fails. The solution: replace the strap or add a ground wire.

For what it's worth, I'm thinking adding the wire will fix the blinking the headlights do when I hit a bump too hard.

Sparksalot · April 7, 2019

I'm glad I found this thread. I was convinced the de-commissioning process for my PPV disabled the reverse lights. I had none at all, then one day the were on continuously. I replace the underhood fuse block, which replaced the reverse relay too. That did the trick. GM calls it a "junction block"

GM 22798217 Engine Wiring Harness Junction Block

Colton Christman · July 28, 2021

On 4/6/2019 at 10:29 PM, Sparksalot said:

I'm glad I found this thread. I was convinced the de-commissioning process for my PPV disabled the reverse lights. I had none at all, then one day the were on continuously. I replace the underhood fuse block, which replaced the reverse relay too. That did the trick. GM calls it a "junction block”

did you have to have yours programmed by the dealer? My 2014 ppv has this same issue, and I can get the junction box brand new from a gm parts supplier but it states it must be programmed. Just trying to see if this is true or not