Test Description
The number below refers to the step number on the diagnostic table.
- 3: This step verifies that the malfunction is present.
DTC P1404
| Step | Action | Values | Yes | No |
|---|---|---|---|---|
| Schematic Reference: Engine Controls Schematics Connector End View Reference: Engine Controls Connector End Views or Powertrain Control Module (PCM) Connector End Views |
||||
| 1 | Did you perform the Diagnostic System Check - Vehicle? | - | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information |
| 2 | Is DTC P0641 also set? | - | Go to DTC P0641 | Go to Step 3 |
| 3 |
|
1% | Go to Step 4 | Go to Step 6 |
| 4 |
|
15% | Go to Step 5 | Go to Step 7 |
| 5 |
|
- | Go to Step 6 | Go to Diagnostic Aids |
| 6 |
|
1% | Go to Step 7 | Go to Step 10 |
| 7 | Connect a test lamp between the 5-volt reference circuit of the EGR valve and the low reference circuit of the EGR valve. Does the test lamp illuminate? |
- | Go to Step 8 | Go to Step 9 |
| 8 | Connect a 3-amp fused jumper wire from the 5-volt reference circuit of the EGR valve to the EGR valve position signal circuit. Is the EGR Position Sensor parameter on the scan tool more than the specified value? |
99% | Go to Step 14 | Go to Step 12 |
| 9 | Connect a test lamp between the 5-volt reference circuit of the EGR valve and a good ground. Does the test lamp illuminate? |
- | Go to Step 11 | Go to Step 13 |
| 10 | Test the EGR valve position signal circuit for a short to voltage. Refer to Circuit Testing
and Wiring Repairs
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 19 | Go to Step 16 |
| 11 | Test the low reference circuit of the EGR valve for an open or for high resistance. Refer to Circuit Testing
and Wiring Repairs
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 19 | Go to Step 16 |
| 12 | Test the EGR valve position signal circuit for high resistance or for a high resistance short to ground. Refer to Circuit Testing
and Wiring Repairs
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 19 | Go to Step 16 |
| 13 | Test the 5-volt reference circuit of the EGR valve for an open or for high resistance. Refer to Circuit Testing
and Wiring Repairs
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 19 | Go to Step 15 |
| 14 | Test for an intermittent and for a poor connection at the EGR valve. Refer to Testing for Intermittent Conditions and Poor Connections
and Repairing Connector Terminals
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 19 | Go to Step 17 |
| 15 | Test all 5-volt reference circuits for a short to voltage. Refer to Circuit Testing
and Wiring Repairs
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 19 | Go to Step 16 |
| 16 | Test for an intermittent and for a poor connection at the powertrain control module (PCM). Refer to Testing for Intermittent Conditions and Poor Connections
and Repairing Connector Terminals
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 19 | Go to Step 18 |
| 17 | Replace the EGR valve. Refer to Exhaust Gas Recirculation (EGR) Valve Replacement
. Did you complete the replacement? |
- | Go to Step 19 | - |
| 18 | Replace the PCM. Refer to Control Module References
in Computer/Integrating Systems for replacement, setup, and programming. Did you complete the replacement? |
- | Go to Step 19 | - |
| 19 |
|
- | Go to Step 2 | Go to Step 20 |
| 20 | Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed? |
- | Go to Diagnostic Trouble Code (DTC) List - Vehicle in Vehicle DTC Information | System OK |