Thick Film Ignition Circuit

Slide 59 of 123

Notes:

This schematic shows component arrangement in a typical Ford ignition. The PIP signal is first sent to the ignition control module, and passes through the module to the PCM.

The PCM uses PIP and several other signal inputs to calculate the best ignition timing for operating conditions. Then it sends a Spark OUTput (SPOUT) signal to the module to control timing. The module fires the coil off the leading edge of the SPOUT signal. (Some PCMs can also control primary dwell in systems with Computer Controlled Dwell (CCD).

If the SPOUT input is lost, the module will fire the coil directly off the PIP signal, and the engine will run at a fixed, base timing. If this occurs, the system will store a diagnostic trouble code.

Quick Tip: The PIP signal is also used to close the fuel pump relay. A quick way to test for a PIP signal is to see if you have fuel pressure! ( while cranking)