Circuit/System Testing
- With the ignition ON and the engine OFF, observe the DTC information on the scan tool.
- Disconnect the EGR harness connector and measure the EGR 5 volt Reference circuit for 4.8-5.2 volts.
- If the voltage is less than 4.8 volts test the EGR Valve 5 Volt Reference circuit for an open, high resistance, a short to ground, or a short to the EGR Low Control circuit.
- If the voltage is more than 5.2 volts test the EGR Valve 5 Volt Reference circuit for a short to voltage or a short to the EGR High Control circuit.
- Using a 3 amp fused jumper wire connect the EGR 5 Volt Reference circuit to the EGR Position Signal circuit, and observe the EGR Position Sensor parameter for more than 4.9 volts
- If the EGR Position Sensor parameter is less than 4.9 volts test the EGR Position Signal circuit for an open or high resistance or a short to ground.
- Using a 3 amp fused jumper wire connect the EGR High Control circuit to the EGR Low Control circuit at the EGR harness connector. Command the EGR Valve to 10% while monitoring the EGR Position Sensor parameter. The EGR Position Sensor parameter should remain at 0%.
- If the EGR Position Sensor parameter is more than 0% test the EGR Position Signal circuit for a short to the EGR High Control circuit.
- If all circuits test OK, replace the EGR Valve.