gmc Workshop Repair Guides

GMC Workshop Service and Repair Manuals

Sensors and Switches - Restraint Systems > < Engine Controls - Service Engine Soon Light, DTC 22-TPS|Page 313
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Knock Sensor: Description and Operation

ESC Wiring Diagram

The Electronic Spark Control (ESC) system is comprised of a knock sensor, the ESC module, and the ECM. As the knock sensor detects engine knock, it
sends a voltage signal to the ECM. The ECM responds by retarding the ignition timing until the knocking ceases. As detonation is reduced, the ECM
advances the timing again in small increments back to the pre-programmed point for that engine speed and load.

Sensors and Switches - Restraint Systems > < Engine Controls - Service Engine Soon Light, DTC 22-TPS|Page 313