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EGR Valve: Testing and Inspection

EGR VALVE INSPECTION

Resistance Inspection


NOTE: Perform the following test only when directed.

1. Disconnect the negative battery cable.










2. Inspect resistance of the EGR valve coils.
- If not as specified, replace the EGR valve.
- If as specified, carry out the "Circuit Open/Short Inspection".

Circuit Open/Short Inspection

1. Disconnect the PCM connector.




2. Inspect the following wiring harness for open or short (continuity check).

Open circuit

- If there is no continuity, the circuit is open. Repair or replace the harness.
- EGR valve terminal E (harness-side) and PCM terminal 4E
- EGR valve terminal A (harness-side) and PCM terminal 4H
- EGR valve terminal B (harness-side) and PCM terminal 4K
- EGR valve terminal F (harness-side) and PCM terminal 4N
- EGR valve terminal C or D (harness-side) and main relay terminal C (harness-side)

Short circuit

- If there is continuity, the circuit is shorted. Repair or replace the harness.
- EGR valve terminal E (harness-side) and GND
- EGR valve terminal A (harness-side) and GND
- EGR valve terminal B (harness-side) and GND
- EGR valve terminal F (harness-side) and GND
- EGR valve terminal C or D (harness-side) and power supply

3. Remove the EGR valve, and inspect for any damage or clogging.
- If there is no damage or no clogging, replace the EGR valve.