DTC Troubleshooting
DIAGNOSIS PROCEDURE - DTC P0402 EXHAUST GAS RECIRCULATION (EGR) FLOW EXCESSIVE DETECTED (LEAKAGE)
| Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
| 1 | Perform an On-Board Diagnostic (OBD II) System Check. Was the check performed? |
- | Go to Step 2. | Go to "ON-BOARD DIAGNOSTIC (OBD II) SYSTEM CHECK ". |
| 2 |
Does the Actual EGR Position follow the Desired EGR Position? |
25%, 50% 75%, 100% | Go to Step 19. | Go to Step 3. |
| 3 |
Does the test light illuminate? |
- | Go to Step 4. | Go to Step 5. |
| 4 |
After command is raised, is the voltage displayed on the voltmeter vary between specified values? |
0~5V | Go to Step 6. | Go to Step 7. |
| 5 | Repair the open or poor connection in the EGR ground circuit as needed. Is the repair complete? |
- | Go to Step 19. | - |
| 6 | With a test light connected to ground, probe the EGR valve wiring harness connector terminal 3. Dose the test light illuminate? |
- | Go to Step 8. | Go to Step 9. |
| 7 | With a test light connected to ground, probe the EGR valve wiring harness connector terminal 1, without commanding the EGR valve with scan tool. Dose the test light illuminate? |
- | Go to Step 10. | Go to Step 11. |
| 8 | Check the signal circuit for a short to voltage and repair as needed. Is the repair complete? |
- | Go to Step 19. | Go to Step 12. |
| 9 | With a voltmeter connected to the ground, probe the 5 V reference circuit at terminal 4 of the EGR valve wiring harness connector. Is the voltage near the specified value? |
5V | Go to Step 13. | Go to Step 14. |
| 10 | Check the control circuit for a short to voltage and repair as needed. Is the repair complete? |
- | Go to Step 19. | Go to Step 12. |
| 11 | With a test light connected to B+ and again probe the control circuit at terminal 1. Dose the test light illuminate? |
- | Go to Step 15. | Go to Step 16. |
| 12 |
Is the repair complete? |
- | Go to Step 19. | - |
| 13 | Check the EGR ground circuit for poor connection or proper terminal tension at the ECM and repair as needed. Is the repair complete? |
- | Go to Step 19. | Go to Step 17. |
| 14 | Check the 5 V reference circuit for a short to voltage and repair as needed. Is the repair complete? |
- | Go to Step 19. | Go to Step 12. |
| 15 | Check the control circuit 1 for short to ground and repair as needed. Is the repair complete? |
- | Go to Step 19. | Go to Step 12. |
| 16 | Check the control circuit at terminal 1 for an open or poor connection at EGR valve connector and repair as needed. Is the repair complete? |
- | Go to Step 19. | Go to Step 18. |
| 17 |
Is the repair complete? |
- | Go to Step 19. | - |
| 18 | Check the ECM connector for a poor connection and repair as needed. Is the repair complete? |
- | Go to Step 19. | - |
| 19 |
Does the scan tool indicate that this diagnostic has run and passed? |
- | Go to Step 20. | Go to Step 2. |
| 20 | Check if any additional DTCs are set. Are any DTCs displayed that have not been diagnosed? |
- | Go to applicable DTC TABLE . | System OK |