DTC P0091:00 [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5]

id0102h9009100

DTC P0091:00

Fuel pressure regulator control circuit low input
DETECTION CONDITION
•  When the PCM turns the spill valve control solenoid valve off but the spill valve control solenoid valve control circuit voltage is low for 5 s, the PCM determines that the spill valve control solenoid valve control circuit has a malfunction.
MONITORING CONDITIONS
―  The following conditions are met:
•  Engine speed: 5,700 rpm or less
•  Battery voltage: 10.5 V or more
Diagnostic support note
•  This is a continuous monitor (CCM).
•  The check engine light illuminates if the PCM detects the above malfunction condition during the first drive cycle.
•  FREEZE FRAME DATA (Mode 2)/Snapshot data is available.
•  DTC is stored in the PCM memory.
FAIL-SAFE FUNCTION
•  Stops high pressure fuel pump control
•  Limits intake air amount
POSSIBLE CAUSE
•  High pressure fuel pump connector or terminals malfunction
•  PCM connector or terminals malfunction
•  Short to ground in wiring harness between high pressure fuel pump terminal B and PCM terminal 1EF
•  Open circuit in wiring harness between the following terminals:
―  High pressure fuel pump terminal A—PCM terminal 1EE
―  High pressure fuel pump terminal B—PCM terminal 1EF
•  Spill valve control solenoid valve (built-into high pressure fuel pump) malfunction
•  Fuel injector relay malfunction
•  Open or short to ground in wiring harness between fuel injector relay and PCM
•  PCM malfunction

Diagnostic Procedure

STEP

INSPECTION

ACTION
1
VERIFY FREEZE FRAME DATA (MODE 2)/SNAPSHOT DATA HAS BEEN RECORDED
•  Has the FREEZE FRAME DATA (Mode 2)/snapshot data been recorded?
Yes
Go to the next step.
No
Record the FREEZE FRAME DATA (Mode 2)/snapshot data on the repair order, then go to the next step.
2
VERIFY RELATED SERVICE INFORMATION AVAILABILITY
•  Verify related Service Information availability.
•  Is any related Service Information available?
Yes
Perform repair or diagnosis according to the available Service Information.
•  If the vehicle is not repaired, go to the next step.
No
Go to the next step.
3
INSPECT HIGH PRESSURE FUEL PUMP CONNECTOR CONDITION
•  Switch the ignition off.
•  Disconnect the high pressure fuel pump connector.
•  Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
•  Is there any malfunction?
Yes
Repair or replace the connector and/or terminals, then go to Step 8.
No
Go to the next step.
4
INSPECT PCM CONNECTOR CONDITION
•  Disconnect the PCM connector.
•  Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
•  Is there any malfunction?
Yes
Repair or replace the connector and/or terminals, then go to Step 8.
No
Go to the next step.
5
INSPECT SPILL VALVE CONTROL SOLENOID VALVE CONTROL CIRCUIT FOR SHORT TO GROUND
•  Verify that the high pressure fuel pump and PCM connectors are disconnected.
•  Inspect for continuity between high pressure fuel pump terminal B (wiring harness-side) and body ground.
•  Is there continuity?
Yes
Refer to the wiring diagram and verify whether or not there is a common connector between high pressure fuel pump terminal B and PCM terminal 1EF.
If there is a common connector:
•  Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to ground.
•  Repair or replace the malfunctioning part.
If there is no common connector:
•  Repair or replace the wiring harness which has a short to ground.
Go to Step 8.
No
Go to the next step.
6
INSPECT SPILL VALVE CONTROL SOLENOID VALVE CIRCUIT FOR OPEN CIRCUIT
•  Verify that the high pressure fuel pump and PCM connectors are disconnected.
•  Inspect for continuity between the following terminals (wiring harness-side):
―  High pressure fuel pump terminal A—PCM terminal 1EE
―  High pressure fuel pump terminal B—PCM terminal 1EF
•  Is there continuity?
Yes
Go to the next step.
No
Refer to the wiring diagram and verify whether or not there is a common connector between the following terminals:
•  High pressure fuel pump terminal A—PCM terminal 1EE
•  High pressure fuel pump terminal B—PCM terminal 1EF
If there is a common connector:
•  Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for an open circuit.
•  Repair or replace the malfunctioning part.
If there is no common connector:
•  Repair or replace the wiring harness which has an open circuit.
Go to Step 8.
7
INSPECT SPILL VALVE CONTROL SOLENOID VALVE
•  Reconnect all disconnected connectors.
•  Inspect the spill valve control solenoid valve.
•  Is there any malfunction?
Yes
Replace the high pressure fuel pump, then go to the next step.
(See HIGH PRESSURE FUEL PUMP REMOVAL/INSTALLATION [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5].)
No
Inspect and perform the following:
•  Fuel injector relay
•  Wirnging harness between fuel injector relay and PCM (open or short to ground)
―  If there is any malfunction:
•  Repair or replace the malfunctioning part according to the inspection results, then go to the next step.
―  If there is no malfunction:
•  Go to the next step.
8
VERIFY DTC TROUBLESHOOTING COMPLETED
•  Always reconnect all disconnected connectors.
•  Clear the DTC from the PCM memory using the M-MDS.
•  Perform the KOEO or KOER self test.
•  Is the same DTC present?
Yes
Repeat the inspection from Step 1.
•  If the malfunction recurs, replace the PCM.
Go to the next step.
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 [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5].)
No
DTC troubleshooting completed.