STEP 1. Check harness connector B-16 at EGR valve for damage.
STEP 2. Check the EGR valve.
(1) Disconnect the EGR valve connector B-16.
(2) Measure the resistance between EGR valve side connector terminal No. 2 and either terminal No. 1 or terminal No. 3.Standard value: 20 - 24 Ω [at 20°C (68°F)]
(3) Measure the resistance between EGR valve side connector terminal No. 5 and either terminal No. 4 or terminal No. 6Standard value: 20 - 24 Ω [at 20°C (68°F)]
Is the measured resistance between 20 and 24 Ω [at 20°C (68°F)]?
Go to Step 3. Replace the EGR valve. Then go to Step 11.
STEP 3. Measure the power supply voltage at EGR valve harness side connector B-16.
(1) Disconnect the connector B-16 and measure at the harness side.
(2) Turn the ignition switch to the "ON" position.
(3) Measure the voltage between terminal No. 2, No. 5 and ground.- Voltage should be battery positive voltage.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
Is battery positive voltage (approximately 12 volts) present?
Go to Step 5. Go to Step 4.
STEP 4. Check harness connector A-37X at MFI relay for damage.
STEP 5. Check harness connector B-26 at ECM for damage.
STEP 6. Measure the power supply voltage at ECM harness side connector B-26.
(1) Disconnect the connector B-26 and measure at the harness side.
(2) Turn the ignition switch to the "ON" position.
(3) Measure the voltage between terminal (No. 31, No. 32, No. 47, No. 48) and ground.- Voltage should be battery positive voltage.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
Is battery positive voltage (approximately 12 volts) present?
Go to Step 7. - Repair harness wire between EGR valve connector and ECM connector because of open circuit or short circuit to ground.
- EGR valve connector B-16 (terminal No. 1) and ECM connector B-26 (terminal No. 31).
- EGR valve connector B-16 (terminal No. 3) and ECM connector B-26 (terminal No. 32).
- EGR valve connector B-16 (terminal No. 4) and ECM connector B-26 (terminal No. 47).
- EGR valve connector B-16 (terminal No. 6) and ECM connector B-26 (terminal No. 48).
- Then go to Step 11.
STEP 7. Check harness connector A-37X at MFI relay for damage.
STEP 8. Check for harness damage between MFI relay connector A-37X (terminal No. 2) and EGR valve connector B-16 (terminal No. 2, No. 5).
STEP 9. Check for harness damage between EGR valve connector and ECM connector.
STEP 10. Check the trouble symptoms.
STEP 11. Test the OBD-II drive cycle.
(1) Carry out a test drive with the drive cycle pattern. Refer to Diagnostic Function - OBD-II Drive Cycle - Pattern 3 . (2) Check the diagnostic trouble code (DTC).
Is DTC P0489 set?
Retry the troubleshooting. The inspection is complete.