Ignition Timing Control System: Notes

Ignition timing control system controls ignition timing by matching vehicle operating conditions to preprogrammed timing advance and retard specifications. These parameters are stored in PCM memory. PCM uses input from camshaft and crankshaft sensors, coolant and various other sensors to determine advance requirements.

Ignition timing is controlled by PCM according to engine operating conditions. Optimum ignition timing for various driving conditions is preprogrammed and stored in PCM. PCM receives and processes electrical signals from various sensors to determine present driving conditions. PCM will then select optimum timing signal for present conditions and send voltage signal to power transistor to control timing advance and detonation retard operation (if equipped).