Circuit Description
The pressure control (PC) valve is used to adjust supply pump discharge amount so as to adjust common rail pressure. The discharge amount from the supply pump to the common rail is determined by PC valve current timing.
The DTC will set when the engine control module (ECM) detects an excessively high signal voltage on the PC valve 2 sensor signal circuit.
Conditions for Running the DTC
| • | The battery voltage is more than 10 volts. |
| • | There are no CKP sensor faults. |
| • | The ignition is ON. |
| • | The injection pump operating normally. |
Conditions for Setting the DTC
Abnormally high driving voltage with the PC valve ON.
Action Taken When the DTC Sets
| • | The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails. |
| • | The ECM limits fuel delivery. |
Conditions for Clearing the MIL/DTC
| • | The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail. |
| • | A current DTC, Last Test Failed, clears when the diagnostic runs and passes. |
| • | Clear the MIL and the DTC with a scan tool. |
Diagnostic Aids
Inspect for the following conditions:
| • | Poor connection at the ECM |
| Inspect the harness connectors for backed-out terminals, improper mating, broken locks, improperly formed or damaged terminals, and poor terminal-to-wire connection. |
| • | Damaged harness |
| Inspect the wiring harness for damage, shorts to ground, shorts to battery, and open circuits. If the harness appears to be OK, observe the PC valve display on the scan tool while moving connectors and wiring harnesses related to the PC valve sensor. A change in the PC valve scan tool display will indicate the location of the fault. |
Step | Action | Value | Yes | No |
|---|---|---|---|---|
Schematic Reference: Engine Controls Schematics | ||||
1 | Does the DTC set while the ignition is ON or the engine is running? | -- | Go to Step 2 | Go to Intermittent Conditions |
2 |
Does the resistance measure within the specified range? | 0.9-1.3 ohms | Go to Step 3 | Go to Step 7 |
3 |
Does the voltage measure less than the specified value? | 1 V | Go to Step 5 | Go to Step 4 |
4 | Repair the short to battery positive (B+) on the PC valve input circuit to ECM on the PC valve harness. Did you complete the repair? | -- | Go to Step 10 | -- |
5 |
Does the DTC reset? | -- | Go to Step 8 | Go to Step 6 |
6 |
Does the voltage measure less than the specified value? | 1 V | Go to Step 10 | Go to Step 9 |
7 | Replace the PC valve assembly. Did you complete the replacement? | -- | Go to Step 10 | -- |
8 | Replace the ECM. Did you complete the replacement? | -- | Go to Step 10 | -- |
9 | Repair/replace the PCV harness. Did you complete the action? | -- | Go to Step 10 | -- |
10 | Clear all DTCs. Does the DTC reset while the ignition is ON or the engine is running? | -- | Go to Step 1 | Go to Step 11 |
11 | Did any other DTCs set? | -- | System OK | |
