Before diagnosing starter problems, ensure the battery is fully charged. If the starter motor does not turn at all when the switch is operated, confirm that the shift lever is in Neutral or Park for automatic transmissions or the clutch pedal is depressed for manual transmissions. Verify that the battery is charged and that all cables, both at the battery and starter solenoid terminals, are clean and secure. If the starter motor spins but the engine is not cranking, the over-running clutch in the starter motor is slipping and the starter motor must be replaced. If the starter motor does not operate at all but the solenoid clicks when the switch is actuated, then the problem could lie with the battery, the main solenoid contacts, the starter motor itself or a seized engine. If the solenoid cannot be heard when the switch is actuated, possibilities include a bad battery, a burned fusible link, a defective starter relay, or a defective starter solenoid. To check the solenoid, connect a jumper lead between the battery (+) and the ignition switch terminal on the solenoid. If the starter motor operates, the solenoid is OK and the problem is likely the ignition switch, Neutral start switch or wiring. If the starter motor still does not operate, remove the starter/solenoid assembly for disassembly, testing, and repair. If the starter motor cranks the engine at an abnormally slow speed, first confirm that the battery is charged and all terminal connections are tight. A partially seized engine, or one with the wrong viscosity oil, will crank slowly. Run the engine until normal operating temperature is reached, then disconnect the coil wire from the distributor cap and ground it on the engine. Connect a voltmeter positive lead to the battery positive post and the negative lead to the negative post. Crank the engine and take the voltmeter readings as soon as a steady figure is indicated. Do not allow the starter motor to turn for more than 15 seconds at a time. A reading of nine volts or more, with the starter motor turning at normal cranking speed, is normal. If the reading is nine volts or more but the cranking speed is slow, the motor is faulty. If the reading is less than nine volts and the cranking speed is slow, possibilities include burned solenoid contacts, a bad starter motor, a discharged battery, or a bad connection.
Posted by ToyotaPartsDeal Specialist