Powertrain Control Module

The cruise control system uses the PCM to maintain desired vehicle cruise speed. PCM controls fuel injection pump that is mounted on top of the engine under the intake manifold. PCM also monitors vehicle speed and cruise control operation. The fuel injection pump operates in response to accelerator control system. The accelerator control system consists of an Accelerator Pedal Position (APP) module. APP module sends signals to the PCM that control the fuel injection pump. The PCM assembly contains a low speed limit which will prevent system engagement with vehicle speed less than 25 MPH.

PCM will inhibit cruise control under the following conditions:

• Vehicle speed is less than 25 MPH.
• Selector lever is in Park, Reverse, Neutral, or Low position.
• Low engine RPM.
• High engine RPM (fuel cut-off).
• Vehicle speed is too high.
• An over or under charged battery voltage condition exists.
• Anti-lock brake system/traction control system is active for more than 2 seconds.