Note: Before you begin, please refer to the warnings given in Section. "Safety first!" and in section 1.
1. If the starter does not turn at all when the ignition is on, on models with an automatic transmission, make sure the gear selector lever is in the "Park" or "Neutral" ("P" or "N") position.
2. Make sure the battery is fully charged and that all wires - both on the battery and on the starter solenoid terminals - are clean and secure.
3. If the starter rotates at the required speed, but the engine does not start, then the overrunning clutch is probably slipping - in this case, the starter must be replaced (other possible causes: the starter mounting bolts have become loose; missing teeth on the flywheel ring gear or drive disk).
4. If, when the ignition is turned on, the starter does not work at all, but the traction relay clicks, then the cause is either in the battery, or in the main contacts of the traction relay, or directly in the starter (or in the engine itself).
5. If the click of the traction relay armature is not heard when the ignition is turned on, then the battery is faulty, there is an open circuit, or the traction relay itself is faulty.
6. To test the relay, connect it with a jumper (with fuses) positive battery terminal (+) with ignition socket clamp (small clamp) on the traction relay. If the starter now works. then the traction relay is working properly, and the problem is either in the ignition socket or in the gear selector lever position sensor (automatic transmission), or in the electrical wiring.
7. If the starter still does not work, remove it (see Section 8). You can check the brushes and the commutator (see section 9), but if the problem persists, the starter motor should be replaced or taken to an electrical specialist for inspection and repair.
8. If the starter turns the engine shaft very slowly, first make sure that the battery is charged and the connecting clamps are tightened. The cause may also be partial seizure of the engine or increased viscosity of the oil in it.
9. If the engine is in good condition and the oil viscosity is normal, but the engine cranking speed is still slow, then the traction relay contacts are probably burnt out, the starter motor is faulty, or there is a poor internal connection.