P0490-EGR SOLENOID CIRCUIT SHORT CIRCUIT
For a complete wiring diagram Refer to Section 8W
- When Monitored:
With the ignition on and the ECM EGR Solenoid command on.
- Set Condition:
The ECM detects excessive current on the EGR Solenoid Control circuit.
| Possible Causes |
| INTERMITTENT CONDITION |
| (K35) EGR SOLENOID CONTROL CIRCUIT SHORTED TO VOLTAGE |
| EGR SOLENOID |
| ENGINE CONTROL MODULE |
Diagnostic Test
1. CHECK FOR ACTIVE DTCNOTE: If the ECM detects and stores a DTC, the ECM also stores the engine/vehicle operating conditions under which the DTC was set. Some of these conditions are displayed on the scan tool at the same time the DTC is displayed.
NOTE: Before erasing stored DTCs, record these conditions. Attempting to duplicate these conditions may assist when checking for an active DTC.
Turn the ignition on.
With the scan tool, erase ECM DTCs.
Perform several ignition cycles, turning the ignition off for at least 10 seconds between each ignition cycle.
Monitor the scan tool for ECM DTCs.
Did this DTC set again?
Yes
- Go To 2
No
- Refer to the *CHECKING FOR AN INTERMITTENT DTC Diagnostic Procedure. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING)
2. CHECKING FOR OTHER DTCS
NOTE: An open ASD power supply to the ECM will cause multiple DTC's including this DTC to set.
NOTE: Check the ECM for other DTC's. If other DTC's are set with this DTC refer to the symptom list and perform the CHECKING THE ECM POWER AND GROUND CIRCUITS test before continuing.
If the ECM power and ground circuits are functioning properly continue with this test.
Yes
- Go To 3
3. EGR SOLENOID CONTROL CIRCUIT SHORTED TO VOLTAGE
Turn the ignition off.
Remove the EGR Solenoid from the PDC.
Disconnect the ECM harness connector.
Remove the ASD Relay from the PDC.
Connect a jumper wire between cavity 30 and cavity 87 of the ASD Relay connector.
Turn the ignition on.
Measure the voltage of the EGR Solenoid Control circuit.
Is the voltage above 1.0 volt?
Yes
- Repair the EGR Solenoid Control circuit for a short to voltage.
- Perform the ECM Verification Test Ver. 1 (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).
No
- Go To4
4. EGR SOLENOID
Install a substitute EGR Solenoid in place of the vehicle's EGR Solenoid.
NOTE: Ensure the ECM and EGR Solenoid harness connectors are connected.
Turn the ignition on.
With the scan tool, check for this DTC to set again.
Did this DTC set again?
Yes
- Replace and program the Engine Control Module in accordance with the Service Information.
- Perform the ECM Verification Test Ver. 1 (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).
No
- Replace the EGR Solenoid.
- Perform the ECM Verification Test Ver. 1 (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).