DTC P0404: Exhaust Gas Recirculation (EGR) Open Position Performance: Troubleshooting
TROUBLESHOOTING CHART
| Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
| 1 | Perform an On-Board Diagnostic (OBD) 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 value? |
0 -≈ 5 V | 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. Does 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 a repair necessary? |
- | Go to Step 19 | Go to Step 12 |
| 9 | With a voltmeter connected to the ground, probe the 5 volt reference circuit at terminal 4 of the EGR valve wiring harness connector. Is the voltage near the specified value? |
5 V | Go to Step 13 | Go to Step 14 |
| 10 | Check the control circuit for a short to voltage and repair as needed. Is a repair necessary? |
- | 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 a repair necessary? |
- | Go to Step 19 | Go to Step 17 |
| 14 | Check the 5 volt reference circuit for a short to voltage and repair as needed. Is the repair necessary? |
- | Go to Step 19 | Go to Step 12 |
| 15 | Check the control circuit at terminal 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 |