With Voltmeter Test Procedure

This test requires a digital volt-ohmmeter with an appropriate low voltage scale such as 73 Digital Multimeter 105-R0051 or equivalent. The meter must read within 0.01 millivolt. Also required is a shunt assembly similar to that shown in the illustration.

1. Turn the ignition OFF and make sure there are no electrical loads on. After determining that the compartment lamp is turning off properly, disconnect the engine compartment lamp miniature bulb.
2. Check the battery voltage. If the voltage is under 11.5 volts, charge the battery to above 11.5 volts.
3. Disconnect the battery ground cable.







4. Connect the shunt assembly as shown.

CAUTION: Do not crank the engine, it could destroy the shunt. Also do not use the shunt to measure starting currents.

5. Connect the voltmeter leads to shunt as shown. With this size shunt (50 mV = 50 amps) and voltmeter, a direct current drain measurement can be made.
6. The current reading (current drain) should be less than 0.05 amps. If it exceeds 0.05 amps it indicates a constant current drain which could cause a discharged battery. Possible sources of current drain may be a vehicle lamp (glove - compartment, underhood, luggage compartment, etc.) that does not turn off. If the problem is not a lamp, remove the fuses from the interior fuse junction panel one at a time until the cause of the drain is located. If drain is still undetermined, remove fuses one at a time at the main fuse junction panel to find the problem circuit.