1981 300sdl 15 pin dashboard plug

[JMARINE]

Hello, I really need some help here. I have a 1981 300SDL everything on dashboard worked until after someone installed a radio. Now I have no dash lights, no oil pressure read, no fuel gage, no temp. I think the 15 pin plug wires are wrong. The problem is I only have 13 wires and the colors don't match any schematic. I was hoping someone here could help with pin placement. The 13 wires are:

green, blue/black, green/blue, double wire blue, blue/red, double wire Black/blue, white/blue, brown/red, brown/red/white, white/violet, double wire gray/blue, blue/white, and green/brown, There is no plain brown wire to put at pin #15 as most schematics call for. This is an early 1981 first registered in 1980, any suggestions?

[meltedpanda]

was this a recent addition?
Brown is always ground on the MB so it would seem you have lost your ground? Did they attach it to the radio?

Try running a temporary ground from the dash pod metal frame to a know ground, see if that corrects the issue

I assume you checked the fuses

[aluminum]

If your right about the 15 Pin Hook up to the Cluster you have problem all right
Some Body Shop books show the Schematic's
1 Way to deal with is to go to a self serve salvage Yard , they are full of early Diesels and just snip off a pin Hook-up with the wires still attached both sides
of the plug
" been their and done this " and that works sometime to at least get the wires correct or check if the match . Try for the same year model you can search online for the car you need a fresh one with the cluster still in

I don't Know why they would disconnect the Pin connection ? perhaps looking for a Hot lead ?
The Ground mentioned is a Good tip check that out if possible

[jsb357]

all the diagrams i found show no brown wire in the connector.


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[Diseasel300]

The 300SDL was an '86/87 model year car. An '81 would be a 300SD (not long wheelbase) if it isn't an engine-swapped car. There are considerable differences in the wiring between '81-85 cars and '86-91 cars, make sure you're looking at the correct diagrams for what your car is. If this was originally a gas car that's been swapped with a diesel engine, you need to find the original wiring diagram for the car and compare what you have against what that diagram shows.