Temp Gage issue


New member
Mar 16, 2007
RO Number
Port gages (both helms) are only showing low readings. Engines are both running fine (not hot). No issues on Stbd side. I swapped Port and Stbd temp sensors at manifold and the issue did NOT follow the swap.

Improbable that both gages would go bad at same time. Suspect a wiring issue.

Recommendations on what to do next?
If I were to independently disconnect 1 Gage at a time would that help me diagnose the issue, or do both Gages have to be hooked up for 1 to function?
(Carver 3607AC)

Sure would be easier not to have to snake a new wire all the way up to the bridge Is my thinking...
Interesting discovery while the electrical dummy (me) was troubleshooting today.... these are 4 stud Water Temp guages (not counting 2 mounting studs), when the 3 stud combo plug is removed from either of the gauges (upper helm Port side vs lower helm Port side) the other gauge appears to work fine (reads 160 degrees, idling at the dock). With all Wires hooked up both gages only raise up to 100 degrees. Consistent behavior each time I modify one or the other hookup. What would cause that behavior?

When the 4th stud wiring (independently wired) is on/off there is no effect on gauge readings, so I am devising this is for the Panel lights....

Note: Later I will verify that the 160 degree reading diminishes once the engine cools down. If so, since I always navigate from the bridge I am simply going to leave the lower helm gauge disconnected until this is figured out.
Gage confirmed to operate normally when wired alone.

I suspect that when I replaced the sensors a SINGLE station version was provided instead of the DUAL station version needed. West Marine tech may have blown the lookup on this one. Ordered new sensors from my mechanic. I’ll install next week and hopefully resolve the problem.