• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
• | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
• | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
---|---|---|---|---|
Ignition Voltage | P2009* | P2008 | -- | P2076 |
IMT/IMRC Control Circuit | P2009, P2076 | P2008 | P2010 | P2076 |
IMT/IMRC Signal Circuit | P2077 | P2076, P2077, P2078 | P2076, P2077, P2078 | P2076 |
IMT/IMRC Ground | -- | P2076, P2077, P2078 | -- | P2076 |
*Opens the fuse that supplies voltage to the IMT/IMRC solenoid. |
An intake manifold runner control (IMRC) valve is used to change the intake manifold plenum configuration. When the IMRC valve is open, the intake manifold is configured to one large plenum. When the IMRC valve is closed, the intake manifold is configured to two smaller plenums. The IMRC valve improves engine performance at low and high engine speeds.
Ignition voltage is supplied directly to the IMRC solenoid. The engine control module (ECM) controls the solenoid by grounding the control circuit with a solid state device called a driver. The driver is equipped with a feedback circuit that is pulled-up to a voltage. The ECM can determine if the control circuit is open, shorted to ground, or shorted to a voltage by monitoring the feedback voltage.
The IMRC valve also contains a position sensor which is used to detect the actual position of the IMRC valve in relation to its commanded position. The ECM supplies the IMRC position sensor with a 5-volt signal circuit and the position sensor uses a common ground circuit. The position sensor enables the ECM to detect a physically broken or stuck IMRC valve.
• | The ignition is ON or the engine is operating. |
• | The IMRC solenoid has been commanded ON and OFF at least once during the ignition cycle. |
• | The DTCs run continuously once the above condition is met. |
The ECM detects that the commanded state of the driver and the actual state of the control circuit do not match for greater than a cumulative of 50 seconds.
DTCs P2008, P2009, and P2010 are Type C DTCs.
DTCs P2008, P2009, and P2010 are Type C DTCs.
If the condition is intermittent, move the related harnesses and connectors, with the engine idling, while monitoring the scan tool circuit test status parameters for the component. A circuit test status parameter will change from OK or Not Run to Fault if there is a condition with the circuit or a connection.
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Control Module References for scan tool information
⇒ | If the test lamp does not illuminate, repair the open/high resistance in the ground circuit. |
⇒ | If less than the specified range, repair the short to ground open/high resistance on the ignition 1 voltage circuit. Replace the fuse, if necessary. |
⇒ | If the test lamp remains ON all the time, test the control circuit for a short to ground. If the circuit tests normal, replace the ECM. |
⇒ | If the test lamp remains OFF all the time, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the ECM. |
⇒ | If the voltage is not within the specified range, replace the ECM. |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
• | Control Module References for engine control module replacement, setup, and programming |