P02E1 2018 GMC Sierra Code - Intake Air Flow Valve Control Performance

The intake airflow valve is a throttle plate actuator and is used to achieve high exhaust gas recirculation rates. It increases the pressure difference between exhaust and intake so that the appropriate exhaust quantity can be mixed with the intake air. The intake airflow valve contains a contactless inductive throttle position sensing element that is managed by a customized integrated circuit. The throttle position sensor is mounted within the valve assembly and is not serviceable. The Engine Control Module (ECM) supplies the valve assembly with a 5 V reference circuit, a low reference circuit, an H-bridge motor directional control circuit, and an asynchronous signal/serial data circuit. The asynchronous signal means communication is only going from the valve assembly to the ECM. The valve assembly cannot receive data from the ECM over the signal/serial data circuit. The throttle position sensor provides a signal that changes relative to the throttle blade angle. The throttle position sensor information is transmitted between the valve assembly and the ECM on the signal/serial data circuit. The ECM decodes the serial data signal into separate voltages which are displayed on a scan tool as the voltage inputs from TP sensors 1 and 2. The Diagnostic Trouble Code (DTC) will be set when the desired Throttle Position and the actual Throttle Position is greater than 10%.

• Faulty Throttle Body Assembly
• Throttle Body Assembly harness is open or shorted
• Throttle Body Assembly circuit poor electrical connection
• Faulty Engine Control Module (ECM)