DTC P1379 [MZR-CD (RF Turbo)]
id0102f1117700
DTC P1379 |
Fuel injector supply voltages circuit high input |
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DETECTION CONDITION
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• 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.
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POSSIBLE CAUSE
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• 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
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Diagnostic procedure
STEP |
INSPECTION |
ACTION |
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1
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VERIFY FREEZE FRAME DATA HAS BEEN RECORDED
• Has FREEZE FRAME DATA been recorded?
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Yes
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Go to the next step.
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No
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Record the FREEZE FRAME DATA on the repair order, then go to the next step.
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2
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VERIFY RELATED REPAIR INFORMATION AVAILABILITY
• Verify related service repair information availability.
• Is any related repair information available?
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Yes
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Perform the repair or diagnosis according to the available repair information.
• If the vehicle is not repaired, go to the next step.
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No
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Go to the next step.
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3
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VERIFY CURRENT SIGNAL STATUS: IS CONCERN INTERMITTENT OR CONSTANT?
• Connect the M-MDS to the DLC-2.
• Clear the DTC from the PCM memory using the M-MDS.
• Start the engine.
• Is the PENDING CODE for this DTC present?
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Yes
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Go to the next step.
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No
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Intermittent concern exists.
Perform the “INTERMITTENT CONCERN TROUBLESHOOTING”.
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4
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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?
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Yes
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Repair or replace the suspected terminal, then go to Step 9.
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No
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Go to the next step.
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5
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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:
• Is the voltage B+?
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Yes
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Repair or replace the wiring harness for a short to power supply for the suspected cylinder, then go to Step 9.
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No
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Go to the next step.
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6
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INSPECT FUEL INJECTOR
• Inspect the fuel injector.
• Is there any malfunction?
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Yes
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Replace the fuel injector, then go to Step 9.
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No
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Go to the next step.
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7
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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?
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Yes
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Repair or replace the suspected terminal, then go to Step 9.
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No
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Go to the next step.
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8
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INSPECT FUEL INJECTOR FOR OPEN CIRCUIT
• Turn the engine switch to off.
• Inspect for continuity between following terminals (wiring harness-side harness):
• Is there continuity?
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Yes
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Go to the next step.
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No
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Repair or replace the wiring harness for the suspected circuit, then go to the next step.
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9
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VERIFY TROUBLESHOOTING OF DTC P1379 COMPLETED
• Make sure to reconnect all disconnected connectors.
• Clear the DTC using the M-MDS.
• Start the engine.
• Is the PENDING CODE for this DTC present?
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Yes
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Replace the PCM, then go to the next step.
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No
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Go to the next step.
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10
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VERIFY AFTER REPAIR PROCEDURE
• Perform the Repair Verification Drive Mode.
• Are any DTCs present?
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Yes
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Go to the applicable DTC troubleshooting.
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No
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Troubleshooting completed.
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