DTC P0088:00 [PCM (SKYACTIV-X)]

Description	High fuel pressure sensor circuit range/performance problem
Detection condition	Determination conditions	• A condition in which the actual fuel pressure and the target fuel pressure vary for a continuous specified period of time while the fuel pressure feedback amount is maintained high.
	Preconditions	• Engine speed: 500 rpm or more^1 • The following DTCs are not detected: ― High fuel pressure sensor: P0089:00, P0192:00 and P0193:00 ― High pressure fuel pump: P0091:00 and P0092:00 ^1: Standard can be verified by displaying PIDs using M-MDS
	Malfunction determination period	• Specified time
	Drive cycle	• 1
	Self test type	• CMDTC self test
	Sensor used	• High fuel pressure sensor
Fail-safe function	• Inhibits the SPCCI control with a large amount of intake air introduced (lean A/F).
Vehicle status when DTCs are output	• Not applicable
Possible cause	• High pressure fuel pump connector or terminals malfunction • High fuel pressure sensor connector or terminals malfunction • PCM connector or terminals malfunction • High fuel pressure sensor malfunction • Fuel injector malfunction • High pressure fuel pump malfunction ― Relief valve (built-into high pressure fuel pump) malfunction • PCM malfunction

• The PCM calculates the target fuel pressure appropriate to the engine conditions relative to the actual fuel pressure based on the high fuel pressure sensor signal and provides feedback to the high pressure fuel pump control. If the difference between the actual fuel pressure and the target fuel pressure relative to the feedback amount is large, the PCM determines a malfunction in the high fuel pressure sensor and stores a DTC.

1. Warm up the engine to allow the engine coolant temperature to reach 80 °C {176 °F} or more.

2. Start the engine and leave it idling for 1 min.

Note

• The target calculated by the PCM is increased and the DTC P0088:00 determination conditions are met by repeating the Step 3 operation.

3. Shift to 1st gear and accelerate/decelerate the vehicle to 30—50 km/h {19—31 mph}.

Note

• Match the engine coolant temperature in the recorded freeze frame data/snapshot data, the vehicle speed, and engine speed values to the best extent possible while driving the vehicle.

4. Try to reproduce the malfunction by driving the vehicle for 5 min based on the values in the freeze frame data/snapshot data.

PIDs	Reference
FUEL_PRES	(See PID/DATA MONITOR TABLE [PCM (SKYACTIV-X)].)

Step	Inspection	Results	Action
1	PURPOSE: VERIFY RELATED REPAIR INFORMATION OR SERVICE INFORMATION AVAILABILITY • Verify related Service Bulletins, on-line repair information, or Service Information availability. • Is any related Information available?	Yes	Perform repair or diagnosis according to the available information. • If the vehicle is not repaired, go to the next step.
1		No	Go to the next step.
2	PURPOSE: IDENTIFY TRIGGER DTC FOR FREEZE FRAME DATA • Is the DTC P0088:00 on freeze frame data?	Yes	Go to the next step.
2		No	Go to the troubleshooting procedure for DTC on freeze frame data. (See DTC TABLE [PCM (SKYACTIV-X)].)
3	PURPOSE: RECORD VEHICLE STATUS WHEN DTC WAS DETECTED TO UTILIZE WITH REPEATABILITY VERIFICATION • Record the freeze frame data/snapshot data. Note • Recording can be facilitated using the screen capture function of the PC.	—	Go to the next step.
4	PURPOSE: INSPECT FOR OTHER RELATED DTCs • Perform the DTC inspection for the PCM. (See DTC INSPECTION.) • Are any other DTCs displayed?	Yes	Repair the malfunctioning location according to the applicable DTC troubleshooting. (See DTC TABLE [PCM (SKYACTIV-X)].) Go to the next step.
4		No	Go to the next step.
5	PURPOSE: VERIFY CONNECTOR CONNECTIONS • Start the engine. • Access the FUEL_PRES PID using the M-MDS. (See PID/DATA MONITOR INSPECTION.) • Does the PID value fluctuate when the following connectors are shaken? ― High fuel pressure sensor ― PCM	Yes	Repair or replace the applicable wiring harness or connector parts. Go to Troubleshooting Diagnostic Procedure to perform the repair completion verification.
5		No	Go to Troubleshooting Diagnostic Procedure to perform the procedure from Step 1.

• Repair completion verification

Step	Inspection	Results	Action
1	PURPOSE: INSPECT HIGH FUEL PRESSURE SENSOR FOR MALFUNCTION • Inspect the applicable part. (See HIGH FUEL PRESSURE SENSOR INSPECTION [SKYACTIV-X 2.0].) • Is the part normal?	Yes	Go to the next step.
1		No	Repair or replace the malfunctioning location and perform the repair completion verification. (See HIGH FUEL PRESSURE SENSOR/HIGH FUEL TEMPERATURE SENSOR REMOVAL/INSTALLATION [SKYACTIV-X 2.0].)
Repair completion verification 1	PURPOSE: VERIFY THAT VEHICLE IS REPAIRED • Install/connect the part removed/disconnected during the troubleshooting procedure. • Clear the DTC recorded in the memory. (See CLEARING DTC.) • Replicate the vehicle conditions at the time the DTC was detected using the following procedure. ― Implement the repeatability verification procedure. (See Repeatability Verification Procedure.) • Perform the DTC inspection for the PCM. (See DTC INSPECTION.) • Is the same Pending DTC present?	Yes	Refer to the controller area network (CAN) malfunction diagnosis flow to inspect for a CAN communication error. (See CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW [(E)].) If the CAN communication is normal, perform the diagnosis from Step 1. • If the malfunction recurs, replace the PCM, then go to the next step. (See PCM REMOVAL/INSTALLATION [SKYACTIV-X 2.0].)
Repair completion verification 1		No	Go to the next step.
Repair completion verification 2	PURPOSE: VERIFY IF OTHER DTCs DISPLAYED • Perform the DTC inspection. (See DTC INSPECTION.) • Are any other DTCs displayed?	Yes	Repair the malfunctioning location according to the applicable DTC troubleshooting.
Repair completion verification 2		No	DTC troubleshooting completed.

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