My ammeter & coolant temperature gauges have quit responding. Does anyone have "easy" ways to check these circuits before I disassemble the dash? And, if the gauges DO turn out to be bad, where can I get replacements?

Thanks
Geezer

 

I would say you lost ground to part of the dash, any other things stop working?

 

Yep, could be a ground problem. Check that the strap from engine to firewall is there.

 

If the fuel gauge still works, you voltage 'limiter' is still functional. There are two connectors that plug into the back of the flexible circuit that works the gauges & lights. They can come loose, or get 'schmutz' on them that may affect the signal coming in.
I would check the temp gauge by turning the key to ON, and grounding the sending unit wire. If you have a 2.3, it is on the drivers side, below the intake manifold, above the oil filter. If you ground it, the gauge will move to full tilt quickly if it is connected. The ammeter is a different animal, and depends on Voltage difference between the battery and the load to imitate an ammeter. It is not a real ammeter. I just know it is very simple and if it doesn't work, and it is not a gauge problem, it is wire splices or corrosion type damage between the output of the alternator and the load/battery junction. At the 'junction' the alternator output can go to the battery if charging is needed, or power the load. If it goes from the battery, one side of the ammeter is lowered relative to the other and the gauge moves. Probably the poorest explain...
tom

 

on my 89 ranger i had gauges go goofy,,it turned out there is a circuit board under the headlight switch inside dash that went bad,, replaced it all started to work again......