Symptom Related Diagnostic Procedures

OPERATION
- Turn ignition switch to "ON" position, and battery voltage will be applied to primary winding of ignition coil.
- When crankshaft position sensor signal is input to engine control module, engine control module makes ON-OFF control of ignition power transistors one by one.
- When ignition power transistor is turned on, current flows from ignition coil (primary winding) to ground through ignition power transistor.

TROUBLESHOOTING HINTS
1. Engine cranks, but does not start.
(1) Spark is insufficient or does not occur at all (on spark plug).
- Check ignition coil.
- Check crankshaft position sensor (with a built-in distributor).
- Check ignition power transistor.
- Check spark plugs.
- Check spark plug cable.
(2) Spark is good.
- Check ignition timing.

2. Engine idles roughly or stalls.
- Check spark plugs.
- Check ignition timing.
- Check ignition coil.
- Check spark plug cable.

3. Poor acceleration
- Check ignition timing.
- Check spark plug cable.
- Check ignition coil.