Fuel and emission control systems

Egr valve inspection

~1min read
Operation Test

Carry out the EGR Control Inspection. (See EGR Control System Inspection.

  • If not as specified, perform the further inspection for the EGR valve.
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. (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.

- 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.

Test yourself

A quick Mazda 6 quiz: every answer comes with an explanation and a link to the manual page.