Electrical Temp and alt gauge not working

Last summer I noticed both my volt and temp gauge stopped working at the same time and everything else was functioning fine. Over the winter I did some upgrades and replaced all my engine sensors and did some diagnosing.

Grounded out the wire going to temp sending unit and gauge didn’t move

Checked ohm from sending unit wire to #8 pin on white ten pin connector and I have 5ohm

I then checked the female side of the #8 pin connector to the wiring at the dash cluster and it showed 6ohms

Alternator still charges fine and car doesn’t over heat as I have a mechanical temp gauge but it’s driving me nuts that these two gauges don’t work.

I’ve checked all my grounds numerous times and have even added several more. I don’t have any blown fuses and everything in the car works and functions like new except for the volt and temp gauge.

Any ideas? Does anyone have a dash cluster schematic for a 93 mustang
 

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The feed off the same trace segment on the cluster circuit ribbon. My guess is the trace is damaged and needs a solder bridge

They likely aren’t getting power. You can use a 9v battery with aIigator clip leads and clip onto the circuit board where the plug is to power the ribbon on 7 and 3. You should at least see the volt move to 9. If you don’t, either the power or ground trace is broken

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