The PCM uses the EGR position sensor to determine the position of the EGR valve. The PCM sends a reference voltage through the 5-volt reference circuit to the EGR position sensor. The PCM provides a voltage return path for the sensor through the low reference circuit. A variable voltage signal, based on the EGR valve position, is sent from the sensor to the PCM through the EGR position sensor signal circuit.
Removal & Installation
If the EVP sensor is defective the entire EGR valve motor will need to be replaced.
- Remove the air cleaner duct.
- Detach the electrical connector.
- Remove the screws securing the motor, then remove the motor and spacer (if equipped) from the valve.
Installation is the reverse of removal. Tighten the screws to 18 inch lbs. (2 Nm).
- With the ignition OFF, test for less than 1 ohm of resistance between the low reference circuit terminal B and ground. If greater than the specified range, test the low reference circuit for an open or high resistance.
- With the ignition ON, test for 4.8-5.2 volts between the 5-volt reference circuit terminal A and ground. If less than the specified range, test the 5-volt reference circuit for a short to ground or an open/high resistance. If greater than the specified range, test the 5-volt reference circuit for a short to voltage. If a short is not found, the PCM is faulty.
- With the ignition ON, and the EGR valve disconnected, observe that the EGR Position parameter on the scan tool is 0 volt. If the EGR Position parameter is more than 0 volt, test the signal circuit for a short to voltage. If a short is not found, the PCM is faulty.
- With the ignition ON and the EGR valve disconnected, connect a jumper wire between the 5-volt reference circuit terminal A of the EGR valve and the signal circuit terminal C of the EGR valve and observe with a scan tool that the EGR sensor parameter displays 4.98-5.02 volts. If the EGR Sensor parameter is less than 4.98 volts, test the signal circuit for an open, short to ground, or high resistance.
- If all tests are normal, but the sensor is throwing a DTC code, then the sensor is faulty.