DTC P1378:00 [MZR-CD 2.2]

id0102f3149300

DTC P1378:00

Fuel injector supply voltages circuit low input
DETECTION CONDITION
•  The PCM monitors the supply voltage to the fuel injector. If the fuel injector supply voltage is less than 52.4 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 connector or terminal malfunction
•  Short to ground in the wiring harness between the fuel injector No.1 terminal A and PCM terminal 1D
•  Short to ground in the wiring harness between the fuel injector No.2 terminal A and PCM terminal 1A
•  Short to ground in the wiring harness between the fuel injector No.3 terminal A and PCM terminal 1B
•  Short to ground in the wiring harness between the fuel injector No.4 terminal A and PCM terminal 1C
•  Fuel injector malfunction
•  PCM connector or terminal malfunction
•  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”.
(See INTERMITTENT CONCERN TROUBLESHOOTING [MZR-CD 2.2].)
4
INSPECT FUEL INJECTOR CONNECTOR FOR POOR CONNECTION
•  Switch the ignition to ON.
•  Inspect for poor connection. (such as damaged/pulled-out terminals, corrosion).
•  Is there any malfunction?
Yes
Go to the next step.
No
Repair or replace the terminal, then go to Step 8.
5
INSPECT FUEL INJECTORS CIRCUIT FOR SHORT TO GROUND
•  Switch the ignition to off.
•  Inspect for continuity between the following terminals 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
•  Is there continuity?
Yes
Repair or replace the wiring harness for a short to ground, then go to Step 8.
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 8.
(See FUEL INJECTOR REMOVAL/INSTALLATION [MZR-CD 2.2].)
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 terminal, then go to the next step.
No
Go to the next step.
8
VERIFY TROUBLESHOOTING OF DTC P1378:00 COMPLETED
•  Make sure to reconnect all disconnected connectors.
•  Clear the DTC from the PCM memory 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.
(See PCM REMOVAL/INSTALLATION [MZR-CD 2.2].)
No
Go to the next step.
9
VERIFY AFTER REPAIR PROCEDURE
•  Perform the "AFTER REPAIR PROCEDURE".
•  Are any DTCs present?
Yes
Go to the applicable DTC inspection.
(See DTC TABLE [MZR-CD 2.2])
No
Troubleshooting completed.