The instrument cluster night lights in the '85 300TD stopped working a few months ago. The bottom row of status lights work fine.

I've replaced the bulbs, replaced the rheostat, soldered the leads on the rheostat, and checked the fuses. Still no lights.

Are there any other possible causes?

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JWJ
1983 MB 300D - > 430,000 miles - Deep Blue - Bilstein Comforts - 0-60 in 24 seconds - 27MPG
1985 MB 300TD (wagon) - > 275,000 miles - Manila Beige - Thule rack - 0-60 in 18 seconds - 22 - 25MPG
Biodiesel, Mobil Delvac 1, and Viton fuel lines!

I imagine you've checked for 12v at the pin on the cluster connector....I'd start tracing on the circuit board and see where you're losing voltage. Do not just check for continuity...high resisitance will show continuity but not allow enough voltage to light the bulbs.

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1983 380SL
1995 C280
1995 S500 coupe
1990 Mazda Miata
2004 Suzuki Hayabusa

For what its worth I just had a similar issue on my 300E. The gauge lights worked fine but the rest of the dash, center console and rear window switches were out. Turned out to be a small rectangular looking fuse on the back of the cluster. Mine was indicated by a red plug

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88 300E
03 911 C4S
2008 Triumph Speed Triple

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