Output Functionality

PCM outputs are tested for functionality in addition to testing for opens and shorts. When the PCM provides a voltage to an output component, it can verify that the command was carried out by monitoring specific input signals for expected changes. For example, when the PCM commands the Electronic Throttle Control (ETC) Motor to a specific position under certain operating conditions, it expects to see a specific (target) idle speed (RPM). If it does not, it stores a DTC.

PCM outputs monitored for functionality include:

• Fuel Injectors
• Air Pump Switchover Solenoid
• Short Runner Valve Solenoid
• Ignition Coils
• Throttle Body (Electronic Throttle Control/Throttle Position Sensor)
• Purge Solenoid
• EGR Solenoid
• Radiator Fan Control
• Transmission Controls