Passenger side rear twilight is not working for brake light and for reverse but does come on with headlights on and works with turn signals. Drivers side works Perfect. I tried taking the light assemblies out of both and swapping them and the same problem persists. Any good ways to troubleshoot?
Rear taillight brake and reverse not working.
- Thread starter cburton17
- Start date
B
billintomahawk
Guest
I'd start by crawling under to rear and follow the wiring to confirm it is intact and not messed with by someone trying to do a poor job of making a trailer hook up. Varmints and chewed are a second problem to check for. A corrupt plug connection at the light assembly is a third and a good place to check for power and then work forward until you find it.
I sharpened the probe on my multimeter so I could penetrate the insulation on suspect wiring. If one side works and the other doesn't its either after the split side to side or each side is separate. You need the wiring diagram.
Do you have one?
Do a search, many have been posted for tail lights.
diysprinter.co.uk
bill in tomahawk
I sharpened the probe on my multimeter so I could penetrate the insulation on suspect wiring. If one side works and the other doesn't its either after the split side to side or each side is separate. You need the wiring diagram.
Do you have one?
Do a search, many have been posted for tail lights.
T1N 901 903 Sprinter reference material
bill in tomahawk
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Yes, I found the wiring diagram as well as some suspect wiring from a previous owner. The main power line for the left (gray black) had been spliced onto with a wire that ran around the door and then into the the main power for right (gray red). When I removed the splice wire the right side does not light up at all. I tried replacing the fuse but that didn’t help so I guess it is a problem somewhere along the wire harness below. Maybe I should just run splice wires for the brake and backup as well? I know it is suspect but obviously someone before me wasn’t able to solve things the right way.
D
Deleted member 50714
Guest
Curious, did you check G300 ground?
No I didn't. What is G300 exactly ? It's hard to tell from that diagram. Would the door components really have an impact on the taillights?
D
Deleted member 50714
Guest
G300 is a threaded stud and nut to accommodate wire ground terminations associated with tail lamp electrics. Considering location, exposure and vehicle's age, most likely corroded.
Unfortunately, I have been unsuccessful determining it exact location. Solicited help from more knowledgeable members to no avail.
Here's an example in the engine compartment.
Some learning material. Suggest reading last paragraph first.
D
Deleted member 50714
Guest
Assuming "Marker" = Tail light.
B
billintomahawk
Guest
From memory!
Look for a ground on the drivers side on the inside of the body panel below the rear door where the tail light wiring on the passenger tail light crosses to meet the drivers side wiring. Look for an eyelet screwed to the body????
bill
Look for a ground on the drivers side on the inside of the body panel below the rear door where the tail light wiring on the passenger tail light crosses to meet the drivers side wiring. Look for an eyelet screwed to the body????
bill
autostaretx
Erratic Member
A broken (or bad) ground connection can funnel a bulb's current to other bulbs on both this and the other side.
--dick
--dick
maxsawicky
Active member
yes, all other lights work. turn signal, reverse/backup, and brake lights illuminate.
disregard this post. lol. i thought i was replying to my post, almost identical thread. lol
sorry!
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As you mentioned, the odd wiring that you described would have me suspecting a harness problem, or maybe a problem resulting from previous work/repairs. Some of the harness is revealed if you remove the lens unit. There is a rubber grommet that can be removed underneath the vehicle. That will expose a bit of the harness also.
I don't understand "twilight" in the OP.
vic
I don't understand "twilight" in the OP.
vic