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hi 2004 cl600. get a white warning light that says left license fault. i checked the bulb. good. got a new license plate lamp from mercedes. hoping the old fixture was bad. get the same code after installing the new light. the right light lights up and no fault. the left doesn't not light up and throws a code. i'm assuming a cut wire. at first this was intermittent and now i always get the fault when i turn on the lights. i assume it's not a fuse because i believe both left and right license plate lights would be on the same fuse. am i correct. any suggestion on tracking this cut wire down without ripping all the wiring in the trunk apart? i assume the first place to look would be the sheath of wires that that comes out of the right front trunk lid, but they are cover by a sheath and i really don't want to cut into that and make the car look like crap. your suggestions are most welcome. anyone else have this problem before? any way to check this without dismantling everything?
thanks
on a side note. the license plate lamp was extremely hard to remove. somehow the light is a bit larger than the hole in the body. had to pry it out and break it. when i installed the new one i had to grind down some of the plastic edges to get the lamp to fit in through the hole. this should be a 2 minute job. both myself and a non mercedes master mechanic tried and couldn't get the lamp to fit in the hole. is there some type of trick that we are missing, or is there some type of special tool?
Broken wire inside the wire retractor unit. My car had snapped both of them for the tag lights. Gotta open the unit up and repair the wires, if you don't add much bulk to the harness it will fit back together like stock. Not really fun or easy but not too difficult.
joe, i have researched further and found out that mercedes calls the wire retractor unit the wiring harness roller. so i'm good to go. any tips on which wire i'm looking for. i saw two small connectors with 2 small wires each coming out of the retractor. i'm assuming it should be one of those. i will be attempting this next thurs, or so, so wish me luck and thanks for the info.
I don't recall which wires, the circuits are separate for the left and right tag lights so it can tell you which one is out, but I do seem to remember that there was a splice between them.
I had great difficulty with one licence plate light on one car. I chased volts, amps and ohms all round the trunk lid, and all I did was prove that power was getting to the lamp, and the bulb was good. I stripped the bulb holder and cleaned everything to bare metal to no avail. What should have been completely trivial was a cause of great frustration.
In the end I gave up and bought a pair of LED lamps, and never regretted it. Very bright, white, and a great reversing aid in the dark.
nick, thanks for you input. unfortunately i'm not getting current to one side of the plug to my left license plate light so i'm going to have to chase down a probable cut, or frayed wire.
the best
okay was at the mechanic. he checked the splices and wiring from both license plate lamps. it shows the right wiring good and the left no current. he believes the fault is occurring inside the retractor housing, so i told him to leave well enough alone for now. by any chance are there 2 separate fuses accountable for the license plate lights? also where would the fuses be on the car either 2, or probably one.
thanks.
it appears that the only way for me to solve this problem is to buy a new, or possibly used wire retractor unit.
It's not the retractor but the harness inside of it. You can open it up and repair the wires, that's what I had to do. A new retractor will NOT solve your problem, as you don't get new wires with it. It just holds the section of the trunk harness that could otherwise be in the way of the trunk.
i purchased a used wire retractor with all wires attached. my mechanic did a continuity test on all wires and said unit is good. since the wiring harness is complete with all wires on this retractor i would assume it would work. am i mistaken?
p.s. if you remember only one wire on the left license plate lamp was dead. the other had current. don't know if this matters in the final evaluation.
okay after further thought i still believe the break is in splice where the wires come together in the trunk lid. i believe this because the right license plate lamp works and the left license plate lamp has one wire with current and one with no current. therefore it is only logical that there is a break in that one wire where the splice is. i'm pretty confident on my assessment and have ordered some end crimps to reattach the wires at the splice point. if all else fails i have the used retractor with all wires to fall back on.
Mine had pulled the wires apart inside the insulation where they make a U-turn inside the retractor. Was difficult to find, I ended up cutting back the insulation in a few spots until I found no power, then tracing back. Was tedious but at least now I have tag lights.
FWIW, both mine were out, but both wires were broken.
05-14-2017, 11:23 AM
left license plate light inoperative
