Conditions for Clearing the MIL/DTC

WARNING: This page is about a different car, the 2004 GMC Sierra, 2004 GMC Cab & Chassis Sierra, 2004 Chevrolet Silverado, and 2004 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.

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.

DTC P0489

Step	Action	Yes	No
Schematic Reference: Engine Controls Schematics Connector End View Reference: Engine Control Module (ECM) Connector End Views or Engine Controls Connector End Views
1	Did you perform the Diagnostic System Check-Engine Controls?	Go to Step 2	Go to Diagnostic System Check - Engine Controls
2	Turn ON the ignition, with the engine OFF. Command the EGR Solenoid to 50 percent with a scan tool. Does the EGR valve vacuum control solenoid click continuously when commanded with a scan tool?	Go to Step 3	Go to Step 4
3	Observe the Freeze Frame/Failure Records for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records. Did the DTC fail this ignition?	Go to Step 4	Go to Intermittent Conditions
4	Inspect the Fuel HT Fuse. Is the fuse open?	Go to Step 5	Go to Step 6
5	Disconnect the EGR valve vacuum control solenoid. Test the Ignition 1 voltage circuit for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. If a short to ground is found then replace the fuse. Did you find and correct the condition?	Go to Step 14	Go to Step 10
6	Disconnect the EGR valve vacuum control solenoid. Connect a test lamp between the ignition 1 voltage circuit of the EGR valve vacuum control solenoid and a good ground. Turn ON the ignition with the engine OFF. Does the test lamp illuminate?	Go to Step 7	Go to Step 8
7	Connect a test lamp between the Ignition 1 voltage circuit of the EGR valve vacuum control solenoid and the control circuit of the EGR valve vacuum control solenoid. Command the EGR solenoid to 100 percent with a scan tool. Does the test lamp illuminate?	Go to Step 10	Go to Step 9
8	Repair the open ignition 1 voltage circuit. Refer to Connector Repairs in Wiring Systems. Did you complete the repair?	Go to Step 14	-
9	Test the control circuit of the EGR valve vacuum control solenoid for an open or high resistance. Refer to Circuit Testing and to Connector Repairs in Wiring Systems. Did you find and correct the condition?	Go to Step 14	Go to Step 11
10	Test for an intermittent and for a poor connection at the EGR valve vacuum control solenoid. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Replace the fuse if necessary. Did you find and correct the condition?	Go to Step 14	Go to Step 12
11	Test for an intermittent and for a poor connection at the ECM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition?	Go to Step 14	Go to Step 13
12	Replace the EGR valve vacuum control solenoid. Refer to Exhaust Gas Recirculation (EGR) Valve Solenoid Replacement . Replace the fuse if necessary. Did you complete the replacement?	Go to Step 14	-
13	Replace the ECM. Refer to Engine Control Module (ECM) Replacement . Did you complete the replacement?	Go to Step 14	-
14	Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records. Did the DTC fail this ignition?	Go to Step 2	Go to Step 15
15	Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed?	Go to Diagnostic Trouble Code (DTC) List	System OK