okgolti

My dome light turns 'on' when front passenger door is open but will not turn
'on' when driver door is open.
The switch from the driver door has tested okay by hooking this on passenger side.
I suspect a grounding fault, and if it is, I wouldn't know how to fix it.
Does anybody know the solution to this? Will appreciate any suggestions.

mercedes w123

Hello kind sir,

I would advise the following few things. Please do not feel insulted if the following sounds to simple I don't know how skilled you are.
Check the connectors of the wires these things are a main source of electrical failure since small wire diameters tend to corrode trough there.
Second of all if the wire passes trough any hinges or moving parts check there it is not uncommon that the movement of pedals sometimes crushes a wire that has gotten loose.
If none of the above is true you should just follow the wire by hand and see if it isn't broken anywhere (it also tends to rub open against any metal it is exposed to like holes it passes trough that are missing the rubbers.

anyway good luck and please let us know where the fault was

okgolti

Mercedes w123..... I appreciate your suggestions. Once weather here
warms up, I will get the steering undercover out and trace the wire and follow it
to the end. SOmeone from another forum had suggested that the end of this wire
might have been unplugged accidentally.
I hope it is nothing more than that and will let you know what I uncover.

Thanks

Rmac58

I agree, the usual culprit in a situation like this is a door jamb related problem. You may want to remove the door light switch at the "A" pillar, for lack of a better term, and inspect there. Not sure if removing the kick panel, or "steering undercover" as you refer to it, will show anything. I would think the wire would disappear up the "A" pillar to the light switch.

As mentioned, keep us posted.

okgolti

Can't wait for warmer weather to work on this. I am almost convinced the problem will
be with wiring between the door switch and wherever its end connects to which likely could be the buzzer box.

I have already removed the door 'push button' switch and moved it to the passenger side just to test if the switch is not broken. The switch is okay and so the problem lies with
the lead wires.

Appreciate your suggestion and will check if the wire just didn't make it up the pillar to the
light switch. Thanks, will report my progress.