'89 & '90 Inst. light cluster circuits look the same in Bentley manual diagrams...

+12 comes in on brown wire via cluster Conn. 31 socket 10. That's the round plug with the half-moon key in center.

Ground is via black wire leaving via cluster Conn. 32 socket 4. Smaller crescent shaped plug.

If you have some wires, put 12v on PIN 31/10 (match pin to brown wire socket on plug), and ground PIN 32/4 (black wire on plug).

If no lights then, must be a board circuit open. Or all 3 bulbs are out. You cleaned the contacts. Did you check bulb continuity or put voltage on them directly?


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Bruce Young, 940-NA, 240s galore (one V8 just sold), '73 142, '71 144 (ex circle track car in CT), '67 144 (new), 122 '63 to '67