replaced rheostat now fuel guage no workie!
 

1982 300td wagon
I removed my instrument cluster sunday night to replace the rheostat and in the process the housing that holds all of the wired pins together (15) came apart. Spent the entire day monday trying to figure out where everything goes. So far the only thing that doesn't work is the fuel indicator (hoping the reserve light still works)and the seatbelt light w/ buzzer. The connector pin counts 1-15 ommitting #13. There are 16 possible wire holes with 15 wires to fill the spots and the diagram I have from Haynes says to ommit #9. Other items like brake wear indicators I really don't know if they work yet either.

Heres what I interpreted from the wiring diagrams. I have the Haynes manual and I also called Haynes to get a more specific diagram emailed to me.

Pin #, wire colors and functions best as I can figure:

1 white blue High beams (working)
2 green glow plug timer relay (working)
3 blue black fuel tank guage (not working)
4 blue green fuel reserve light (not sure)
5 black blue aux fan? (not sure)
6 red blue charge indicator (not sure)
7 blue alternator warning (not sure)
8 brown red brake sensor (not sure)
9 blank
10 brown red white parking brake (working)
11 grey green violet light switch conn (working)
12 grey blue inst lights (working finally)
13 black green combo switch (working) all hazards and turn signals working
14 black white combo switch (working)
15 ground (working)

I have rewired this thing and double checked it 5 times and it is exactly as the book says it should be. I am sure at this point I a doing something stupid but I just don't realize it yet. Hoping someone can point out any discrepancies to help me.

Now I am really confused! I went to the salvage yard and looked at the wiring harness for 2 different 82 mercedes 300td's and they are the same as the way I wired mine. So if it's wired correctly why would my fuel gauge and seat belt light and door buzzer not work?

sloved my own problem. In the future when they say unplug the battery then I will probably do it. My problem was a bad fuel sending unit which was fine before I removed the instrument cluster.... and also a bad buzzer box (not sure what it's called but it buzzes when you first turn the ignition on) under the the driverside kick panel located right in front of the cruise control box and the same color (silver) only smaller. Evidently leaving the power hooked up shorted out both items. I was fortunate enough to have two wagons side by side so I could swap parts till I figured it out.

Hope my dumb mistakes helps someone else from making the same.:D