Have just acquired a late (1996) w124 Diesel Kombi, UK spec but I'm sure it will be similar to US spec in the areas of interest.

First problem is the central locking at the driver's door. Sometimes it works the locks and sometimes it does not. I've stripped the door down, checked the actuator and put it together again. After that it would lock the doors, but when you unlocked it the locks other than the driver door would only go up when you opened the driver door. Now it's just completely dead. I think I may have a short in the loom that is affected by opening the door. I'd like to replace that part of the loom (from the door lock actuator to the most convenient point) to eliminate it.

Does anybody know if there is a connector that would allow me to replace that part of the loom as a unit If there is no connector I'd replace the wires all the way from the actuator to the point where they join the main loom if I can get to it if anybody knows where that is and if you can get at it

That's the first problem. Second is the fuel gauge and the oil pressure gauge. The fuel indication keeps dropping to zero when you are driving. Also the oil pressure goes to max (3) when you turn the ignition on before you start the engine. Seems like some kind of short circuit. Could be the wiring again or is that what happens when the instrument cluster fails

I would just do the repair on the door loom if it was me .Then go from there to the gauges. Its possible that after the finisher is removed from the side wall by the foot controls you should find a connector at the rear for assembly ,the loom then runs through a concertina grromet that will be fixed to both the door, and the car frame . The wire joint or connection could be in the door, or inside the car .There must be one for assembly , good luck

Just an aside...what's a Diesel Kombi? Can you post a picture?

The wiring bundle from the door is often a problem at the hinge pillar. You'll probably find that there's a break there. And if there's one break, there will be others in time, affecting your windows and mirrors as well as your locks. When this happens, I splice in lengths of high strand count, silicone insulated wire. This is much more flexible than standard automotive wiring, so it solves the problem forever. Something like this:

https://www.ebay.com/itm/BNTECHGO-16-Gauge-Silicone-Wire-Kit-Ultra-Flexible-10-Color-High-Resistant-200/202155889107?hash=item2f116e11d3:g:7KMAAOSw8axaPRwF

On the 124 cars, there is a couple of crimped joints in the power and ground wires to the electric pump that lives under the back seat. In the rear passenger footwell on the right side of the car, you have to pull up the carpet to get into the plastic wire tray, unwrap the tape around that joint, and re-do those connections. Typically they get wet and corrode and then pump operation for the door locks gets very weird and flaky.

__________________
Respectfully,
/s/
M. Dillon
'87 124.193 (300TD) "White Whale", ~392k miles, 3.5l IP fitted
'95 124.131 (E300) "Sapphire", 380k miles
'73 Balboa 20 "Sanctification"
Charleston SC