Component Description

Fig.9 Power Distribution Center (PDC):

The PCM regulates the ignition system. The PCM supplies battery voltage to the ignition coil through the Auto Shutdown (ASD) Relay.

The PCM controls ignition timing by turning on and off a transistor in the distributor.

During the crank-start period the PCM maintains spark advance at 9° BTDC. During engine operation the following inputs determine the amount of spark advance provided by the PCM.
- Intake air temperature.
- Coolant temperature.
- Engine RPM.
- Intake manifold vacuum.

The PCM also regulates the fuel injection system.