DTC P1264 Without RPO CTF
Circuit Description
A hydraulic piston and two-way valve (TWV) or solenoid valve have been added to the conventional nozzle. Receiving signals from the engine control module (ECM), the TWV opens and closes to change the pressure in the pressure adjustment chamber on top of the hydraulic piston so that the hydraulic piston operates, thereby ejecting the fuel from the nozzle. If the ECM detects a low voltage condition on the TWV voltage supply circuit of cylinder 1,2 or 3, DTC P1263 will set. If the ECM detects a high voltage condition on the TWV voltage supply circuit of cylinder 1,2 or 3, DTC P1264 will set.
Conditions for Running the DTC
| • | Battery voltage is more than 10 volts. |
| • | There is no engine overspeed condition. |
Conditions for Setting the DTC
The TWV voltage supply circuit is shorted to battery voltage.
Action Taken When the DTC Sets
| • | The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails. |
| • | The ECM limits fuel delivery on cylinders 4, 5, and 6. The ECM stop fuel injection on cylinders 1, 2, and 3. |
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. |
| • | Erratic RPM |
| • | Lack of engine power |
Step | Action | Value | Yes | No | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
Schematic Reference: Engine Controls Schematics | ||||||||||||
1 | Does the scan tool display the DTC while the ignition is ON or the engine is running? | -- | Go to Step 2 | Go to Intermittent Conditions | ||||||||
2 |
Does each voltage measure less than the specified value? | 1 V | Go to Step 3 | Go to Step 4 | ||||||||
3 | Measure voltage at the following points at the ECM connector on the TWV harness:
Does each voltage measure less than the specified value? | 1 V | Go to Step 5 | Go to Step 4 | ||||||||
4 | Repair/replace the TWV harness. Did you complete the action? | -- | Go to Step 5 | -- | ||||||||
5 |
Does the DTC reset? | -- | Go to Step 6 | Go to Step 8 | ||||||||
6 | Replace the ECM. Did you complete the replacement? | -- | Go to Step 7 | -- | ||||||||
7 |
Does the DTC reset? | -- | Go to Step 2 | Go to Step 8 | ||||||||
8 | Did any other DTCs set? | -- | System OK | |||||||||
DTC P1264 With RPO CTF
Circuit Description
The fuel 1 injector drive circuit is a high-voltage supply and drives injectors installed to cylinder 1, 2, and 3. The engine control module (ECM) steps up the battery voltage and supplies the resulted high voltage to the related injectors continuity. If the fuel 1 injector drive circuit supply to the cylinder 1, 2, or 3 is short to voltage circuit or if the injector solenoid control circuit 1, 2, or 3 is shorted to voltage, this DTC will set.
Conditions for Running the DTC
| • | The ignition is ON. |
| • | The battery voltage is between 10-16 volts. |
| • | The engine is running. |
| • | The crankshaft position (CKP) sensor is not failed. |
Conditions for Setting the DTC
The ECM detects that the injector power supply circuit is short to voltage circuit.
Action Taken When the DTC Sets
| • | The ECM illuminates the malfunction indicator lamp (MIL) and reduced engine power indicator lamp, if fitted, when the diagnostic runs and fails. |
| • | The ECM records the operating conditions at the time the diagnostic fails. The ECM stores this information in the Failure Records. |
| • | The ECM disables 1, 2, and 3 injector operation. |
| • | The ECM limits fuel injection quantity for fail-safe operation. |
| • | The ECM closes the exhaust gas recirculation (EGR) valve and holds to close position. |
| • | The ECM inhibits cruise control. |
Conditions for Clearing the DTC
| • | The MIL resets when the ignition is turned OFF. |
| • | A current DTC, Last Test Failed, clears when the diagnostic runs and passes. |
| • | Clear the MIL and the DTC with a scan tool. |
Step | Action | Values | Yes | No |
|---|---|---|---|---|
Schematic Reference: Engine Controls Schematics | ||||
1 | Did you perform the Diagnostic System Check - Control Module? | -- | Go to Step 2 | |
2 |
Does the DTC fail this ignition? | -- | Go to Step 3 | Go to Intermittent Conditions |
3 |
Are the voltage measures more than the specified value? | 1 V | Go to Step 4 | Go to Step 6 |
4 |
Did you find and correct the condition? | -- | Go to Step 7 | Go to Step 5 |
5 |
Did you find and correct the condition? | -- | Go to Step 7 | Go to Diagnostic Aids |
6 |
Important: The new ECM must be programmed. Replace the ECM. Refer to Engine Control Module Replacement/Restore Fuel Rate Data . Did you complete the replacement? | -- | Go to Step 7 | -- |
7 |
Did the DTC fail this ignition? | -- | Go to Step 2 | Go to Step 8 |
8 | Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed? | -- | System OK | |
