DTC P1379:00 [MZR-CD 2.2]


id0102f3149400

DTC P1379:00

Fuel injector supply voltages circuit high input

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 ignition switch is on, the PCM determines that there is a malfunction in the fuel injector circuit.
Monitoring conditions
―  Following conditions are met:
•  Battery voltage: more than 8 V
•  Time from switch the ignition to on: 2 sec.
Diagnostic support note
•  The MIL illuminates if the PCM detects the above malfunction condition in first drive cycle.
•  PENDING CODE is available if the PCM detects the above malfunction condition during the first drive cycle.
•  FREEZE FRAME DATA (mode2) and snapshot data are available.
•  The DTC is stored in the PCM memory.
POSSIBLE CAUSE
•  Fuel injector or terminal malfunction
•  Short to power supply in the wiring harness between the fuel injector No.1 terminal A and PCM terminal 1D
•  Short to power supply in the wiring harness between the fuel injector No.2 terminal A and PCM terminal 1A
•  Short to power supply in the wiring harness between the fuel injector No.3 terminal A and PCM terminal 1B
•  Short to power supply in the wiring harness between the fuel injector No.4 terminal A and PCM terminal 1C
•  Short to power supply in the wiring harness between the fuel injector No.1 terminal B and PCM terminal 1H
•  Short to power supply in the wiring harness between the fuel injector No.2 terminal B and PCM terminal 1I
•  Short to power supply in the wiring harness between the fuel injector No.3 terminal B and PCM terminal 1F
•  Short to power supply in the wiring harness between the fuel injector No.4 terminal B and PCM terminal 1K
•  Fuel injector malfunction
•  PCM connector or terminal malfunction
•  Open circuit in the wiring harness between the fuel injector No.1 terminal A and PCM terminal 1D
•  Open circuit in the wiring harness between the fuel injector No.2 terminal A and PCM terminal 1A
•  Open circuit in the wiring harness between the fuel injector No.3 terminal A and PCM terminal 1B
•  Open circuit in the wiring harness between the fuel injector No.4 terminal A and PCM terminal 1C
•  Open circuit in the wiring harness between the fuel injector No.1 terminal B and PCM terminal 1H
•  Open circuit in the wiring harness between the fuel injector No.2 terminal B and PCM terminal 1I
•  Open circuit in the wiring harness between the fuel injector No.3 terminal B and PCM terminal 1F
•  Open circuit in the wiring harness between the fuel injector No.4 terminal B and PCM terminal 1K
•  PCM malfunction

Diagnostic procedure

STEP

INSPECTION

ACTION

1
VERIFY FREEZE FRAME DATA (MODE2) OR SNAPSHOT DATA HAVE BEEN RECORDED
•  Have FREEZE FRAME DATA (mode2) or snapshot data been recorded?
Yes
Go to the next step.
No
Record the FREEZE FRAME DATA (mode2) and snapshot data on the repair order, then go to the next step.
2
VERIFY RELATED SERVICE INFORMATION
•  Verify related Service Information availability.
•  Is any related Service Information available?
Yes
Perform repair or diagnosis according to available Service Information.
•  If 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 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?
Yes
Go to the next step.
No
Intermittent concern exists.
Perform the “INTERMITTENT CONCERN TROUBLESHOOTING”.
4
INSPECT FUEL INJECTOR CONNECTOR FOR POOR CONNECTION
•  Switch the ignition 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
•  Switch the ignition to ON (Engine off).
•  Disconnect the PCM connector.
•  Inspect the voltage between following terminals (wiring harness-side) and body ground:
―  Fuel injector No.1 terminal A
―  Fuel injector No.2 terminal A
―  Fuel injector No.3 terminal A
―  Fuel injector No.4 terminal A
―  Fuel injector No.1 terminal B
―  Fuel injector No.2 terminal B
―  Fuel injector No.3 terminal B
―  Fuel injector No.4 terminal B
•  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.
•  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
•  Switch the ignition 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
•  Switch the ignition to off.
•  Inspect for continuity between following terminals (wiring harness-side harness):
―  Fuel injector No.1 terminal A and PCM terminal 1D
―  Fuel injector No.2 terminal A and PCM terminal 1A
―  Fuel injector No.3 terminal A and PCM terminal 1B
―  Fuel injector No.4 terminal A and PCM terminal 1C
―  Fuel injector No.1 terminal B and PCM terminal 1H
―  Fuel injector No.2 terminal B and PCM terminal 1I
―  Fuel injector No.3 terminal B and PCM terminal 1F
―  Fuel injector No.4 terminal B and PCM terminal 1K
•  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 P1379:00 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?
Yes
Replace the PCM, then go to the next step.
No
Go to the next step.
10
VERIFY AFTER REPAIR PROCEDURE
•  Perform the "AFTER REPAIR PROCEDURE".
•  Are any DTCs present?
Yes
Go to the applicable DTC troubleshooting.
No
Troubleshooting completed.