P0489

DTC P0489

CIRCUIT DESCRIPTION
The exhaust gas recirculation (EGR) valve is vacuum operated. Vacuum for the EGR valve control system is supplied by a belt driven vacuum pump. The EGR valve vacuum control solenoid and the EGR valve vacuum vent solenoid work together to control the position of the EGR valve. The EGR valve vacuum control solenoid is supplied with 12 volts through the ignition 1 circuit. The EGR valve vacuum control solenoid is pulse width modulated through the EGR valve solenoid control circuit by the engine control module (ECM). The ECM monitors the voltage on the EGR valve vacuum solenoid control circuit. If the ECM detects a low voltage condition on this circuit, DTC P0489 sets.

CONDITIONS FOR RUNNING THE DTC
- The Engine Run Time parameter is more than 0.5 seconds.
- The Ignition 1 Signal parameter is between 11-18 volts.
- The EGR Solenoid Command parameter is less than 71 percent.

CONDITIONS FOR SETTING THE DTC
The ECM detects a low voltage condition on the EGR valve solenoid control circuit for more than 2 seconds.

ACTION TAKEN WHEN THE DTC SETS
- The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
- The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

CONDITIONS FOR CLEARING THE MIL/DTC
- The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
- A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
- A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
- Clear the MIL and the DTC with a scan tool.

TEST

Steps 1-5:

Steps 6-11:

Steps 12-15: