Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

(Some people have issue connecting. LEMON is investigating. For now, use Firefox or change your DNS server)

Or, hide this message: temporarily or permanently

ECM/PCM Control of Ignition

PCM Inputs And Outputs:




Ignition Schematic:











The Powertrain Control Module (PCM) controls spark advance and fuel injection for all driving conditions. The PCM monitors input signals from the following components as part of its Ignition Control function to determine the required ignition timing:

^ Ignition Control Module (ICM).

^ Engine Coolant Temperature (ECT) sensor.

^ Manifold Absolute Pressure (MAP) sensor.

^ Transaxle Range (TR) switch.

^ Throttle Position (TP) sensor.

^ Vehicle Speed Sensor (VSS).

^ Knock sensor