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 observe the EGR Position Sensor parameter. The EGR Position Sensor parameter should display 0 percent.
- If the EGR Position Sensor parameter is more than 0 percent, test the EGR position sensor signal circuit for a short to voltage or a faulty control module.
- Using a 3-amp fused jumper wire, jumper the EGR 5-volt reference circuit to the EGR position sensor signal circuit at the EGR harness connector and monitor the EGR Position Sensor parameter. The EGR Position Sensor parameter should display 99 percent.
- If the EGR Position Sensor parameter is less than 99 percent test for an open, high resistance or a short to ground in the EGR pintle position signal circuit.
- Disconnect the control module and measure the resistance of the EGR high control circuit and the EGR low control circuit. There should be less than 3 ohms of resistance on each circuit.
- If the resistance is more than 3 ohms, test each circuit for high resistance.
- If all circuits test OK, replace the EGR valve.