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DTC P1379 [MZR-CD (RF Turbo)]

id0102f1117700

DTC P1379 | Fuel injector supply voltages circuit high input
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DETECTION CONDITION | • The PCM monitors the supply voltage to the fuel injector. If the fuel injector supply voltage is more than 107.9 V when the engine switch is on, the PCM determines that there is a malfunction in the fuel injector circuit. Diagnostic support note • The MIL illuminates if the PCM detects the above malfunction condition during the first drive cycle. • The FREEZE FRAME DATA is available. • The DTC is stored in the PCM memory.
POSSIBLE CAUSE | • Fuel injector malfunction • Connector or terminal malfunction • Open circuit in the wiring harness between the fuel injector No.1 terminal B and PCM terminal 42 • Open circuit in the wiring harness between the fuel injector No.2 terminal B and PCM terminal 21 • Open circuit in the wiring harness between the fuel injector No.3 terminal B and PCM terminal 23 • Open circuit in the wiring harness between the fuel injector No.4 terminal B and PCM terminal 40 • Open in the wiring harness between the fuel injector No.1 terminal A and PCM terminal 4 • Open in the wiring harness between the fuel injector No.2 terminal A and PCM terminal 4 • Open in the wiring harness between the fuel injector No.3 terminal A and PCM terminal 4 • Open in the wiring harness between the fuel injector No.4 terminal A and PCM terminal 4 • Short to power circuit in the wiring harness between the fuel injector No.1 terminal B and PCM terminal 42 • Short to power circuit in the wiring harness between the fuel injector No.2 terminal B and PCM terminal 21 • Short to power circuit in the wiring harness between the fuel injector No.3 terminal B and PCM terminal 23 • Short to power circuit in the wiring harness between the fuel injector No.4 terminal B and PCM terminal 40 • Short to power in the wiring harness between the fuel injector No.1 terminal A and PCM terminal 4 • Short to power in the wiring harness between the fuel injector No.2 terminal A and PCM terminal 4 • Short to power in the wiring harness between the fuel injector No.3 terminal A and PCM terminal 4 • Short to power in the wiring harness between the fuel injector No.4 terminal A and PCM terminal 4 • PCM malfunction

Diagnostic procedure

STEP | INSPECTION | ACTION
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1 | VERIFY FREEZE FRAME DATA HAS BEEN RECORDED • Has FREEZE FRAME DATA been recorded? | Yes | Go to the next step.
No | Record the FREEZE FRAME DATA on the repair order, then go to the next step.
2 | VERIFY RELATED REPAIR INFORMATION AVAILABILITY • Verify related service repair information availability. • Is any related repair information available? | Yes | Perform the repair or diagnosis according to the available repair information. • If the vehicle is not repaired, go to the next step.
No | Go to the next step.
3 | VERIFY CURRENT SIGNAL STATUS: IS CONCERN INTERMITTENT OR CONSTANT? • Connect the WDS or equivalent to the DLC-2. • Clear the DTC from the PCM memory using the WDS or equivalent. • Start the engine. • Is the PENDING CODE for this DTC present? | Yes | Go to the next step.
No | Intermittent concern exists. Perform the "INTERMITTENT CONCERN TROUBLESHOOTING". (See INTERMITTENT CONCERN TROUBLESHOOTING [MZR-CD (RF Turbo)].)
4 | INSPECT FUEL INJECTOR CONNECTOR FOR POOR CONNECTION • Turn the engine switch to off. • Inspect for poor connection fuel injector for each cylinder (such as damaged/pulled-out terminals, corrosion). • Is there any malfunction? | Yes | Repair or replace the suspected terminal, then go to Step 9.
No | Go to the next step.
5 | INSPECT FUEL INJECTORS CIRCUIT FOR SHORT TO POWER SUPPLY • Turn the engine switch to the ON position (Engine off). • Disconnect the PCM connector. • Inspect the voltage between following terminals (wiring harness-side) and body ground: - Fuel injector No.1 terminal B - Fuel injector No.2 terminal B - Fuel injector No.3 terminal B - Fuel injector No.4 terminal B - All fuel injector terminals A • Is the voltage B+? | Yes | Repair or replace the wiring harness for a short to power supply for the suspected cylinder, then go to Step 9.
No | Go to the next step.
6 | INSPECT FUEL INJECTOR • Inspect the fuel injector. (See FUEL INJECTOR INSPECTION [MZR-CD (RF Turbo)].) • Is there any malfunction? | Yes | Replace the fuel injector, then go to Step 9.
No | Go to the next step.
7 | INSPECT PCM CONNECTOR FOR POOR CONNECTION • Turn the engine switch to off. • Inspect for poor connection. (such as damaged/pulled-out terminals, corrosion). • Is there any malfunction? | Yes | Repair or replace the suspected terminal, then go to Step 9.
No | Go to the next step.
8 | INSPECT FUEL INJECTOR FOR OPEN CIRCUIT • Turn the engine switch to off. • Inspect for continuity between following terminals (wiring harness-side harness): - Fuel injector No.1 terminal B and PCM terminal 42 - Fuel injector No.2 terminal B and PCM terminal 21 - Fuel injector No.3 terminal B and PCM terminal 23 - Fuel injector No.4 terminal B and PCM terminal 40 - All fuel injector terminals A and PCM terminal 4 • Is there continuity? | Yes | Go to the next step.
No | Repair or replace the wiring harness for the suspected circuit, then go to the next step.
9 | VERIFY TROUBLESHOOTING OF DTC P1379 COMPLETED • Make sure to reconnect all disconnected connectors. • Clear the DTC using the WDS or equivalent. • Start the engine. • Is the PENDING CODE for this DTC present? | Yes | Replace the PCM, then go to the next step. (See PCM REMOVAL/INSTALLATION [MZR-CD (RF Turbo)].)
No | Go to the next step.
10 | VERIFY AFTER REPAIR PROCEDURE • Perform the Repair Verification Drive Mode. (See OBD DRIVE MODE [MZR-CD (RF Turbo)].) • Are any DTCs present? | Yes | Go to the applicable DTC troubleshooting. (See DTC TABLE [MZR-CD (RF Turbo)].)
No | Troubleshooting completed.