86 xjs convertible project dash gauge test

Is there a way to bench test the gauges with a multimeter before reinstalling. Thanks

Hi Rodney - the temp, oil pressure, and fuel tank gauges can be tested by applying battery voltage to one lead, and applying a ground to the other side momentarily - the ground will make the gauge go to the full deflection end (highest temp, highest oil pressure, and full fuel) - use the electrical schematic to find the correct terminal, at the connection jack, for the point to apply battery, and for the point to apply ground - the point to apply ground will be the same point that the wire, from the temp sensor, oil pressure sensor, and fuel gauge float, arrive at the panel jack - the voltage gauge should be able to read close to what a meter shows for the battery level - with the schematic you can also test all your indicator bulbs - there is a ground buss bar that needs to be clean to help with the bulb check - i will leave it to someone else to chime in for the testing of the tach and speed gauges.

I finally got my car running and the dash reinstalled, My temperature gauge climbs slowly, pegs then drifts back to the bottom peg, then repeats, fuel gauge works, amp gauge works, tach works oil pressur doesnt but I mounted an external gauge for back up. So Ill check the other end of the connections and see whats what. All in all it works better than it did and with a few more checks Im confident Ill get it. Only one idiot light now (oxygen sensor) compared to the five that were lit. Thanks for the testing procedures

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Rodney - pull the connector off at the temp sensor for the gauge - watch the gauge and if it still has the movement you described, then you have a faulty wire (or gauge) that is picking up a stray ground with the engine vibration - if no movement on the gauge, once you have removed the connector at the sensor, you have a faulty sensor.

Thanks for the info but I found the problem. Apparently I didnt bleed the system enough and it wasnt reading properly because of air in the system. I have the coolant topped off and air eliminated and now it works as it should. Now on to the oil gauge. Thanks Rod