The below linked Teleflex website contains some troubleshooting guides that should help you out. I think that the ones titled "A Basic Gauge Test" and "Trim Gauges" would be the most helpful.
In short, you test the trim gauge by grounding out the send terminal on the gauge to see if it responds properly, you test the trim sender with an ohmmeter to see if the resistances are correct when the motor is in the UP and DOWN positions, you confirm continuity in the SEND wire between the sender and the gauge, and lastly you confirm that the sender and gauge are both properly grounded. These tests should tell you if you need to get a new gauge, a new sender, or just fix your existing wiring/ground connections.
Anyway, Trim gauge stopped working, did a test on the Trim sending unit with ohmmeter and no matter what the resistance stays the same with the trim up or down.
so my question is, where can i find a new trim sending unit. for an 88merc.
or do all the trim sending units send the same signal so it wouldn't matter what one i get?
