PeachParts Mercedes-Benz Forum - View Single Post - Looking for W123 wiring diagram. Headlamp issue.

jay_bob · #4 01-28-2013, 06:05 AM

I believe I got my copy of the diagram at startekinfo.com, there are 2 documents. One is a schematic (they call it the electrical troubleshooting manual or ETM) and the second is a series of photos and captions that identify the devices and connectors, called the component locations.

The bird is Pelican Parts, the sponsor of the site.

C106 is the big rectangular connector near the steering shaft under the dash. The harness coming down from the steering column switch lands on this connector. The 123 has a very simple electrical system, everything is right there and easy to see under the dash. There is another big connector under the dash, that is C104, that connects the entire rear of the car into the under dash harness.

The lower trim panel on a 123 is easy to remove, 3 cover plugs on the top edge, remove the 3 screws behind the plugs. Then 2 quarter turn plastic fasteners at the lower left (near the e-brake) and lower right (near the go pedal). Once you have that off you can see everything under the dash.

The light switch removes by pulling off the knob and loosening the big nut. Then grab the switch from behind and give the switch housing a twist to release the ears from the dashboard and it will drop down. There should be an insulator over the terminals. Be sure it is in place before dropping out the switch, you don't want to have the 30 terminal hit metal.

Good luck and be safe. But very first thing I would do is check fuse F11, I suspect you won't have to go much further to get lights back.