DTC Troubleshooting: P0490 (182-7)

DTC P0490: EGR valve Circuit Shorted to Power

1. Turn the ignition switch ON (II).

1. Clear the DTC with the HDS.

1. Check for Temporary DTCs or DTCs with the HDS.

Is DTC P0490 indicated?

YES | - | Go to Step 4 .
NO | - | Intermittent failure, system is OK at this time. Check for poor connections or loose terminals at the EGR valve and the ECM.■

1. Turn the ignition switch OFF, and wait 30 seconds.

1. Disconnect the EGR valve 6P connector.

1. At valve side, measure resistance between EGR valve 6P connector terminals No. 4 and No. 6.

Is there about 7 Ω at room temperature?

YES | - | Go to Step 7 .
NO | - | Go to Step 10 .

1. Disconnect ECM connector No. 1 (96P).

1. Turn the ignition switch ON (II).

1. Measure voltage between EGR valve 6P connector terminal No. 6 and body ground.

Is there battery voltage?

YES | - | Repair short to power in the wire between the EGR valve and ECM connector No. 1 terminal No. 48, then go to Step 11 .
NO | - | Go to Step 15 .

1. Replace the EGR valve.

1. Reconnect all connectors.

1. Turn the ignition switch ON (II).

1. Reset the ECM with the HDS.

1. Check for Temporary DTCs or DTCs with the HDS.

Are any Temporary DTCs or DTCs indicated?

YES | - | If DTC P0490 is indicated, check for poor connections or loose terminals at the EGR valve and the ECM, then go to Step 1 . If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.
NO | - | Troubleshooting is complete.■

1. Update the ECM if it does not have the latest software, or substitute a known-good ECM.

1. Check for Temporary DTCs or DTCs with the HDS.

Are any Temporary DTCs or DTCs indicated?

YES | - | If DTC P0490 is indicated, check for poor connections or loose terminals at the EGR valve and the ECM, then go to Step 1 . If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.
NO | - | If the ECM was updated, troubleshooting is complete. If the ECM was substituted, replace the original ECM. ■