'86 W124 300E Wiring Issue

[brandob9]

Hey guys -

I have narrowed one of my electrical demons to the wiring associated with fuse 3. (thanks for the tip of replacing all the fuses) That circuit runs the cluster lights, right side brake and running lights and headlight wipers. I know the fuse and bulbs to be good, leaving the wiring.

I suspect the wires are chafed and grounding somewhere. Where would you start the search?

Or, am I better off doing a redneck version, creating a relayed circuit using the left side as a signal?

Thanks for your help and ideas.

[JCE]

Have you recently worked on your stereo? I had problems like that after my radio was worked on by a shop - turned out to be a wiring problem on the back of the cigar lighter socket, they had mashed the wires back in when doing the re-assembly and the socket wiring was messed up. Mike Tangas helped me trace the fault, moving the socket wires apart solved the problem. May not be the same problem, but it is an easy place to start.

[Ron in SC]

Exactly what problems are you experiencing?

[brandob9]

First guy -
There is an aftermarket stereo. I just bought the car about a week ago without realizing this electrical issue was present. That might be an idea. I'll check whether the cigarette lighter has power.

Second guy -

I have no power to:
- Right side brake light
- Right side running lights
- Cluster lights
- Cluster outside temp gauge

I have replaced the bulbs in question, and replaced all of my fuses. Fuse #3 lasts about 1 second after I rotate the light switch.

[Ron in SC]

Not sure if this has anything to do with your problem but there is a tiny fuse element, part #2015460025, in the instrument cluster. It's behind the cluster, the part that you see looks like a little bulb socket but it's red, it's the only red one back there. It fits into the rear of the cluster like some of the tiny bulbs. I forget which lights in the cluster it affects.

[brandob9]

Is the removal of these clusters like the W126 ones? I only ask as I have a link to a W126 cluster removal.

http://v12uberalles.com/instrument_cluster_removal.htm

[Ron in SC]

See link:
http://www.peachparts.com/Wikka/W124InstCluster