Before diagnosing starter problems, ensure the battery is fully charged. If a malfunction occurs in the starting circuit, do not immediately assume the starter is the issue; first, check that the battery cable clamps are clean and tight, inspect the condition of the battery cables and replace any defective ones, and test the battery's condition, replacing it if necessary. Additionally, examine the starter solenoid wiring and connections, check the tightness of the starter mounting bolts, and inspect the fusible links near the positive battery terminal, repairing any burned links and checking the ignition switch circuit for correct operation. Verify the operation of the transmission range sensor or clutch start switch, ensuring the shift lever is in PARK or NEUTRAL or the clutch pedal is pressed, as these systems must function correctly to provide battery voltage to the ignition solenoid. If the starter does not actuate when the ignition switch is turned to the start position, check for battery voltage to the solenoid to determine if it is receiving the correct voltage signal. If voltage is present but the starter motor does not operate, remove the starter and bench test it. If the starter turns over slowly, check the starter cranking voltage and current draw from the battery, ensuring the voltage does not drop below specified levels and the current draw remains within range. If the starter is receiving voltage but does not activate, remove and check the starter/solenoid assembly, as the solenoid may be defective. In rare cases, ensure the engine is not seized by attempting to rotate the crankshaft pulley. While testing the starter/solenoid assembly on the bench, connect jumper cables to the battery and apply voltage to the solenoid S terminal, observing the movement of the solenoid plunger and pinion drive to determine if the assembly is functioning properly.