I fit a quad gauge from an '86 420SEL so I can use the economy gauge as a boost gauge. To do the swap, I had to move pins in the round 15 pin connector. Pin 2 goes to the previously vacant position 1 for engine temp, pin 3 goes to the now vacant position 2 for fuel level and pin 4 goes to position 3 for low fuel. Position 4 is available for low oil but an 83 617 doesn't have a sensor. Working with that 15 pin connector is quite a PITA. Have a full pin mapping handy because it's difficult to keep the pins seated. And disconnect the battery in case pins touch.

I moved pin 13 to position 4 to use the bulb that aligns with the SD glow window but the key on self test foils the purpose. One option is to reroute the blue wire with white stripe that goes to pin 13 to a bulb socket under the clock for a glow indicator (anyone have a spare SDL warning light strip?). I don't know how to modify the quad gauge board to bypass the POST.

Sixto
83 300SD

I need those pin maps.

If the 85 SE and the 86 SEL have the same warning light strips I might be able to help you.

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84 300SD
85 380SE
83 528e
95 318ic

You can make the maps by comparing diagrams in the FSM.

I need an SDL warning light strip with glow icon.

Sixto
83 300SD

Alas, the S-class cars I saw today at Pick-n-Pull were not diesel.

There's an SDL at the San Jose north lot so I have what I need.

Sixto
83 300SD