Q: How to diagnose and troubleshoot starter problems?
A: Before diagnosing starter problems, ensure that the battery is fully charged. Check shift lever/clutch pedal. Clean and secure cables. If starter motor spins but engine doesn't crank, replace starter motor. If solenoid clicks but motor doesn't operate, check battery, solenoid contacts, motor, or seized engine. If solenoid plunger can't be heard, check battery, fusible link, or solenoid. To check solenoid, connect jumper lead between battery and ignition switch wire terminal. If motor operates, solenoid is fine. If not, check ignition switch, neutral start switch, or wiring. If motor still doesn't operate, remove for testing and repair. If motor cranks slowly, check battery and connections. If engine is seized or has wrong oil, it may crank slowly. To test motor, run engine until normal temp, disconnect coil wire, ground it, connect voltmeter to battery posts, crank engine, take readings. 9 volts or more with normal speed is normal. Less than 9 volts with slow speed may indicate burned contacts, bad motor, discharged battery, or bad connection.