W124 - Weird traits with boot open

[Vectrolosys]

Hello,

This problem relates to a 1991 (August 91 registered) W124 300TE.

If you have the interior light switch on the dash, set to the 'come on with the rear doors and boot open' position, you'll get a strange buzzing from behind the dash (which sounds like a slightly strangled lights on buzzer), the dash tell tail lights, and number plate illumination lights will all illuminate.

This says that something is shorting somewhere. Is it possible that there is a short in the wiring going into the bootlid?

Thanks for any advice,

James

[nick mercedes]

Originally Posted by Vectrolosys

Hello,

This problem relates to a 1991 (August 91 registered) W124 300TE.

If you have the interior light switch on the dash, set to the 'come on with the rear doors and boot open' position, you'll get a strange buzzing from behind the dash (which sounds like a slightly strangled lights on buzzer), the dash tell tail lights, and number plate illumination lights will all illuminate.

This says that something is shorting somewhere. Is it possible that there is a short in the wiring going into the bootlid?

Thanks for any advice,

James

Sometimes the wires in the boot hinges get a bit fraid?

[Vectrolosys]

Originally Posted by nick mercedes

Sometimes the wires in the boot hinges get a bit fraid?

Funnily enough, I've just read that somewhere else. Would make sense from what I have been reading. Looks like I'll be stripping the wiring down and checking it over

[Smiley]

My w124 does exactly the same. I have tracked the problem to the wiring where it goes into the roof at the top of the tailgate - it goes brittle here and cracks. It is not easy to fix unfortunately as it is a bu**er to get the roof lining out and remove the internal connections of the wiring to give enough slack in the wiring to fix it.
So I am afraid to confess that I went for the simple fix and turned the dash switch to the centre off position.
If you figure out a quicker way to fix then pls let me know!
Just out of interest check your number plate bulbs when lifting the tailgate - mine work fine with the tailgate closed - then as it is lifted they go out - another strange symptom of the wiring problem.

The saloons suffer from the same problem - the wires going to the number plate lights go brittle and crack and short - but there the symptoms are limited to the exterior bulbs.

[Vectrolosys]

Originally Posted by Smiley

My w124 does exactly the same. I have tracked the problem to the wiring where it goes into the roof at the top of the tailgate - it goes brittle here and cracks. It is not easy to fix unfortunately as it is a bu**er to get the roof lining out and remove the internal connections of the wiring to give enough slack in the wiring to fix it.
So I am afraid to confess that I went for the simple fix and turned the dash switch to the centre off position.
If you figure out a quicker way to fix then pls let me know!
Just out of interest check your number plate bulbs when lifting the tailgate - mine work fine with the tailgate closed - then as it is lifted they go out - another strange symptom of the wiring problem.

The saloons suffer from the same problem - the wires going to the number plate lights go brittle and crack and short - but there the symptoms are limited to the exterior bulbs.

Funnily enough, that's the route I have taken!! I'm going to have a poke around, but not until later in the summer as my wife is due with our second at any time now.

I had a feeling it would be around the hinge area though, it looks ripe for problems later in life, what with all the movement it has to endure.

I'm popping out in a bit to give it a wash and polish, and check the bulbs over, so will have a look and let you know.

[Vectrolosys]

Hello,

Yep, when I lift the bootlid, with the lights on, the numberplate lights go out.

I managed to remove the trim panel at the rear of the roof, and can see all of the wires in here, however, I haven't attempted to remove any further than this. There is a large wiring block on the passenger side of the car, that has a spur coming off and into the bootlid. I am tempted to work out which one goes where, then run my own wiring loom into the boot lid and down to the various areas it needs to go to. Bit intense, but could be the only way forward.

James