Egr valve inspection
Carry out the EGR Control Inspection. (See EGR Control System Inspection.
- If not as specified, perform the further inspection for the EGR valve.
- 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. (See PCM REMOVAL/INSTALLATION.)
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.
Short circuit- 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)
- 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.
Test yourself
A quick Mazda 6 quiz: every answer comes with an explanation and a link to the manual page.