W124 300CE Left number plate lamp +ve supply dead

[rayhennig]

A break in the +ve (positive) supply has been verified and, currently, the +ve supply is being taken from the right hand supply. Of course, the warning light shines brightly on the dashboard.

So, I must find where the cable (pink/grey, I think) is broken. It's likely to be somewhere near the boot hinge but it is far from easy to get to the cables without tearing into insulation and conduit..

Does anyone know where the cables run to once they enter the car having passed through the hinge. I need to establish if the supply is good before the hinge. Basically, I want to narrow down the location of the break before I start cutting into insulation.

My hope is that I may be able to draw the cables out, having soldered a flexible cable to one end, find the break, fix it and then draw the cable back using the flexible cable. Then reattach the terminals and all should be fine.

So, please, any insight would be much appreciated.

Thanks in advance and best to all.

RayH

 

[DREAMER NO2]

Ray if i am right that thats how rear number plates light worked from one to the other ..i am on it ...

 

[DREAMER NO2]

I was right and main power is taken from left rear cluster no 58 View attachment 78192 and work piggy back see pic

 

[DREAMER NO2]

Reg plate light 58 is piggy backed for earth only see diagram .

 

[DREAMER NO2]

Ray power is taken via the light control unit back of fuse box the large type relay . Could be just the earth from one light to the other ,,try an extre earth wire

 

[DREAMER NO2]

Main earth point for the reg plate lamps are taken from left hand rear tail light cluster ,, so first check the earth in trunk area near rear lights

 

[rayhennig]

Main earth point for the reg plate lamps are taken from left hand rear tail light cluster ,, so first check the earth in trunk area near rear lights

Thanks Dreamer. I'll get back to that project soon as I've just found a ****** disaster.

I was going to install my nice, new, genuine MB plug leads, cap and rotor and I found that the last cowboys who worked on the car have completely rounded off the rotor arm Allen key slots. Nothing I can do so I've asked a local chum to come up with ideas. Livid. Hopping mad.

More anon.

R

 

[DREAMER NO2]

Ray put super glue in the hex key hole let it set ...then give it a turn it worked on one job i got stuck with

 

[alexanderfoti]

Or hammer a torx bit into it

Or drill the top off with a reversible bit

 

[rayhennig]

Sorry, I never completed this thread. No action yet on the number plate light. It's still wired parallel with the other one and, of course, I have a nice little lamp on the dashboard reminding me! Not a major priority si I'll wait for warmer weather.

And my chum dislodged the rotor arm and all the posh MB HT stuff is working well.

Thanks again.

RayH

 

[DREAMER NO2]

I am sure thats how they are wired ,,,power to the one, and a spur to the other .

 

[alexanderfoti]

I am sure thats how they are wired ,,,power to the one, and a spur to the other .

On cars with bulb out monitoring unit, they are wired independently from the bulb monitoring unit.

 

[DREAMER NO2]

Well mine W124 as a bulb out warning light in the dash ..this car as never beem operated on fron new ..And piggy back on the rear number plate lights exist...

 

[alexanderfoti]

All of the ones I have worked have seperate feeds.

 

[EmilysDad]

All of the ones I have worked have seperate feeds.

My W251/R Class must have had separate feeds because it would tell which specific bulb/lamp had failed

 

[mioba]

w251 were a muh modern car full of SAMS, the W124 was (is) a different kettle of fish.

 

[EmilysDad]

w251 were a muh modern car full of SAMS, the W124 was (is) a different kettle of fish.

I was just sayin'

 

[DREAMER NO2]

I was wrong in a way , you can see the piggy back is to earth not the possitive. fig 58 .

 

[alexanderfoti]

The piggy back is the ground, not the power though? Unless we are talking about different things

 

[DREAMER NO2]

As you said=the piggy is ground