Electronic Ignition (EI) System
Electronic Ignition (EI) System Input And Output Chart:
CIRCUIT OPERATION
The ignition timing is controlled by the Engine Control Module (ECM) to help maintain the best blend of engine performance and emissions under all operating conditions.
The ECM uses several sensors to calculate the amount of timing based on a map stored in its memory. The ECM varies the timing during:
- Starting
- Warm up
- Idle
- Hot engine operation
- Acceleration
- Low battery voltage
- Engine ping
Power Transistor:
POWER TRANSISTOR
The power transistor, located on the back of the passenger's side cylinder head, is a voltage amplifier that allows the signal sent from the ECM to activate the primary circuit in the ignition coils. This induces high voltage in the secondary windings of the coils, providing spark to the plugs.