I have a '05 Yukon XL Danelli that my wife drives and loves. The break light 'bar' above the rear hatch does not light, so I went to replace the bulbs. Once I removed the light bar I could not figure out how to gain access to the bulbs, is this a sealed unit that gets replaced or are the individual bulbs replacable? Does anyone have any experience with the bulb replacement? This is a great forum, thanks for your help. Jerry
3rd break light bulb replacement
- Thread starter grandslam
- Start date
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OmarR
Full Access Member
It is an LED setup, so I guess you could tear it open and try replacing each LED, but there are MANY in there. It's just easier to replace the whole unit, but that's about $120.
Also, make sure you check the fuse, it's the 10A [Veh CHMSL] in your driver fuse panel.
Also, make sure you check the fuse, it's the 10A [Veh CHMSL] in your driver fuse panel.
Rivieraracing
Full Access Member
Yeah, I would agree, put a volt meter on the connection to the 3rd brake light and make sure if there is even power going to it when you push in the brake pedal before you take it apart or even replace it. Probably just a burnt fuse or a bad connection, those LED's usually last a long time.
Rollin Thunder
Full Access Member
mine lights up , but only if i hit the brake. i thought it was a tail light an brake light but i guess not, have a bud or your wife hit the brake and see if it lights up then.
Thanks for the info guys. Makes sense since I did not see any to access the bulbs once I removed the light. I would have thought the guy in the auto parts store would have told me that. I will test the circuit before I invest in the whole unit, a fuse sure would be a lot cheaper. Thanks again, Jerry
if the 3rd brake light fuse is out... then your tail lights fuse would be out as well, considering it is only one fuse for all the break lights.
Rivieraracing
Full Access Member
Not fully true, at least on my rig. My 3rd brake light was out while the other brake lights worked just fine, my 3rd brake light is tied into the cruise control circuit and when my 3rd light was out I didn't realize I didn't have CC. Confused the dealer when he was trying to fix my trailer brake controller problem. They check the light, checked all the brake related stuff in the way of fuses and relays, and then finally started pulling all the fuses and that was when they ran across the CC fuse burnt up. A new fuse later and I was off and running with 3 working brake lights!! Bada bing!!:thumbsup:
jey_
Full Access Member
The brake lights on two different circuits (and fuses) could be by design. That way if you blow a fuse on one you still have SOME brake lights. Brake lights are pretty important. Makes troubleshooting a pain though as you can see.
OmarR
Full Access Member
Negative.
Regular brake lights - VEH STOP 15A fuse
Third brake light - VEH CHMSL 10A fuse
Both in drivers fuse panel.
Rivieraracing
Full Access Member
So tell me how what I said was shenanigans when I saw it with my own eyes, I was in the garage for the 45 minutes that the guy was trying to diagnose my truck.
Think about it this way, when you are driving down the road using your cruise control, what happens as soon as you touch your brakes............the cruise control is disabled........so you don't hit the car in front of you because your cruise control was set at 75 and you were wanting to slow down. It didn't make sense at first but when I realized the relation with the 3rd brake light to the CC then it all made sense. Still calling shenanigans??
I wasn't saying you were wrong... I was saying that shenanigans were pulled somewhere to make me wrong.
D.amn CHMSL FUSE!
