- In order to prevent the engine from starting while performing these checks, disconnect the fuel shutoff solenoid connector.
- Inspect all the switches in order to determine the condition.
- The battery must be fully charged. If the battery was recently charged, remove the surface charge, then perform the load test. Refer to Battery Load Testing.
- Ambient temperatures should be at least 15.5 ° C (60 ° F) in order to perform this procedure. Cold weather will cause higher resistance in the circuit.
- Connect a digital multimeter across the battery. It should show at least 12 volts.
- Crank the engine and check the voltage.
- Check the starter ground by connecting the digital multimeter from the negative terminal of the battery to the ground stud of the starter motor field frame.
- Crank the engine. The multimeter should read about 0.2 volt. If the reading is 0.5 volt or higher, there is excessive resistance in the ground circuit.
- If the circuit wires, the connections and the ground circuit are OK, but there is still excessive resistance, repair the starter motor.
Although the starter motor cannot be checked against specifications on the vehicle, a check can be made for excessive resistance in the starting circuit.
The P72 has a mechanical interlock in the steering column that does not allow the ignition switch to turn to START unless the transmission is in P (Park) or N (Neutral). The P92, equipped with the 37-MT, has an electronically-controlled transmission that has a neutral start switch built into the VIM.
NOTICE: Do not operate the starter motor continuously for more than 30 seconds without pausing to allow it to cool for at least two seconds. Overheating from excessive cranking will seriously damage the starter motor.
If there is more than a two volt drop, there is excessive resistance in the circuit. Check for loose, corroded or dirty connections or frayed cables.
