2009 Tahoe Backup Light

[KenJackman]

OK guys I am stumped. I have a 2009 Tahoe Z71 with trailer towing package. I am the original owner. No mods. I noticed yesterday that the driver's side backup light is out. I pulled the bulb, it looked good, I applied 12v to it on my workbench and it checked good. I cleaned the bulb socket, put the bulb back into the Tahoe and it still did not work. I pulled out my multimeter and it shows 12v at the two terminals in the socket when the Tahoe is put in reverse. For the heck of it I swapped the left and right backup bulbs and that fixed nothing. The driver's side bulb worked fine in the passenger side but the passenger side bulb did not light up in the driver's side either. Not sure what to chase as I see a solid 12v on the socket pins with my multimeter when it goes into reverse. I've even tried bending the pins up on the bulb and the socket thinking it might not be making good contact with the socket pins but no joy. Any ideas?

 

[wsteele]

OK guys I am stumped. I have a 2009 Tahoe Z71 with trailer towing package. I am the original owner. No mods. I noticed yesterday that the driver's side backup light is out. I pulled the bulb, it looked good, I applied 12v to it on my workbench and it checked good. I cleaned the bulb socket, put the bulb back into the Tahoe and it still did not work. I pulled out my multimeter and it shows 12v at the two terminals in the socket when the Tahoe is put in reverse. For the heck of it I swapped the left and right backup bulbs and that fixed nothing. The driver's side bulb worked fine in the passenger side but the passenger side bulb did not light up in the driver's side either. Not sure what to chase as I see a solid 12v on the socket pins with my multimeter when it goes into reverse. I've even tried bending the pins up on the bulb and the socket thinking it might not be making good contact with the socket pins but no joy. Any ideas?

The only thing that comes to mind is maybe you have an intermittent connection in the socket wiring, such that when the bulb is secure in the socket, it is causing an open circuit in the wires connected to it.

 

[KenJackman]

I see that GMPARTSDIRECT has the short entire tail lamp harness for $38.00. I'm inclined to purchase it. The only other thing I'd add is that recently I got the "SERVICE TRAILER BRAKE SYSTEM" warning on the dash a few weeks back and had to replace that relay module. Not sure if there is any relationship between these two events or not. I guess this 2009 Tahoe is beginning to tell me it is time to start shopping for a replacement vehicle!

 

[wsteele]

I see that GMPARTSDIRECT has the short entire tail lamp harness for $38.00. I'm inclined to purchase it. The only other thing I'd add is that recently I get the "SERVICE TRAILER BRAKE SYSTEM" warning on the dash a few weeks back and had to replace that relay module. Not sure if there is any relationship between these two events or not. I guess this 2009 Tahoe is beginning to tell me it is time to start shopping for a replacement vehicle!

If you are willing to sacrifice a bulb for science, you could decapitate it, insert it in the socket and with your voltmeter, see if the bulb inserted in the socket was causing an interruption of the voltage. Might save you say, $32 of the $38...

I have shopped and shopped and when I am intellectually honest (hard to do when staring at a shiny new truck on the lot), nothing beats these NBS and NNBS trucks. I look at a Land Cruiser and the dealer points out the lift gate half goes up to shield the weather when loading and unloading and the window opens independently... well, my Yukon has that too. On and on it goes and when I am done comparing feature to feature and do an honest accounting of how much just about anything that might go wrong will cost (even if I have the dealer fix it), versus the $10K a year I will see in depreciation with just about anything I might get t replace it? I quit shopping for a time.

 

[KenJackman]

I hear you. This is the wife's daily ride and there are other minor things that have popped up recently on this SUV. We are only at 91,000 miles at 11 years of ownership. It has been a good vehicle and relatively issue free until the past year or so. The sales tax alone on a new Yukon Denali is nearly $5k. I can buy a lot of parts for this 2009 for $5k. That plus there is virtually zero inventory in new Yukons right now and no one is dealing on price has me backing away for another year or so until we look again. Obviously one backup light is just a nuisance complaint. My next move is to unplug that short harness and give it a good look and a shot of contact cleaner....quick and easy check. I like the sacrificial bulb idea. Will try to collect one today and give that a try if my harness connection clean and reseat does nothing for me. Maybe a weak ground?

 

[avalonandl]

Test the short harness for connectivity.

 

[petethepug]

OK guys I am stumped. I have a 2009 Tahoe Z71 with trailer towing package. I am the original owner. No mods. I noticed yesterday that the driver's side backup light is out. I pulled the bulb, it looked good, I applied 12v to it on my workbench and it checked good. I cleaned the bulb socket, put the bulb back into the Tahoe and it still did not work. I pulled out my multimeter and it shows 12v at the two terminals in the socket when the Tahoe is put in reverse. For the heck of it I swapped the left and right backup bulbs and that fixed nothing. The driver's side bulb worked fine in the passenger side but the passenger side bulb did not light up in the driver's side either. Not sure what to chase as I see a solid 12v on the socket pins with my multimeter when it goes into reverse. I've even tried bending the pins up on the bulb and the socket thinking it might not be making good contact with the socket pins but no joy. Any ideas?

 

[CaptainAmerica1]

My Silverado did this. Replaced the bulb, cleaned the bulb socket etc.. etc.. finally had to change the short harness and no problems in 4 years.