Volt Meter Gauge: Testing and Inspection

The diagnosis found here addresses an inoperative gauge condition. If the problem being diagnosed is related to gauge accuracy, be certain to confirm proper charging system operation before considering gauge replacement. If no charging system problem is found, the following procedure will help diagnose an inaccurate gauge.
1. Turn the ignition switch to the On position. The voltmeter should read battery voltage. If all gauges except the voltmeter are OK, go to Step 2. If the other gauges are inoperative, see the diagnosis for Printed Circuits.
2. Using an accurate test voltmeter, measure the battery voltage at the battery. Compare this reading to the instrument cluster voltmeter reading. Now, see the Voltmeter Calibration chart in Specifications. If the voltmeter does not perform within the specifications, replace the faulty voltmeter.