DTC P258B:00 [SKYACTIV-D 2.2]

id0102s4221200

DTC P258B:00	Power brake unit vacuum sensor control circuit range/performance problem
DETECTION CONDITION	•  The PCM determines that the measurement performance of the power brake unit vacuum sensor and the vacuum generation performance of the vacuum pump, calculated from the engine speed, are deteriorated.
FAIL-SAFE FUNCTION	•  Not applicable
POSSIBLE CAUSE	•  Vacuum line (between vacuum pump and each solenoid valve) malfunction ―  Vacuum hose breakage, damage ―  Check valve malfunction •  Vacuum line (between vacuum pump and power brake unit) malfunction ―  Vacuum hose breakage, damage ―  Check valve malfunction •  Power brake unit malfunction •  Power brake unit vacuum sensor malfunction •  Oil pressure decrease •  vacuum pump malfunction ―  Vacuum pump deterioration •  PCM malfunction
SYSTEM WIRING DIAGRAM	Not applicable

Diagnostic Procedure

Step	Inspection	Results	Action
1	RECORD VEHICLE STATUS WHEN DTC WAS DETECTED TO UTILIZE WITH REPEATABILITY VERIFICATION Note •  Recording can be facilitated using the screen capture function of the PC. •  Record the freeze frame data/snap shot data.	—	Go to the next step.
2	INSPECT VACUUM HOSE BETWEEN VACUUM PUMP AND SOLENOID VALVE •  Inspect the vacuum hose between the vacuum pump and each solenoid valve (compressor bypass valve, regulating solenoid valve, wastegate solenoid valve) for the following. ―  Connection condition ―  Damage •  Is there a malfunction in the vacuum hose?	Yes	Repair or replace the malfunctioning part Go to Step 8.
		No	Go to the next step.
3	INSPECT VACUUM HOSE BETWEEN VACUUM PUMP AND POWER BRAKE UNIT •  Inspect the vacuum hose between the vacuum pump and the power brake unit for the following. ―  Connection condition ―  Damage •  Is there a malfunction in the vacuum hose?	Yes	Repair or replace the malfunctioning part Go to Step 8.
		No	Go to the next step.
4	INSPECT CHECK VALVE OF VACUUM HOSE •  Inspect the check valve operation of the vacuum hose. (See CHECK VALVE INSPECTION [SKYACTIV-D 2.2].) •  Is the check valve normal?	Yes	Go to the next step.
		No	Replace check valve, then go to Step 8. (See CHECK VALVE REMOVAL/INSTALLATION [SKYACTIV-D 2.2].)
5	INSPECT POWER BRAKE UNIT •  Inspect the power brake unit operation. (See POWER BRAKE UNIT INSPECTION.) •  Is power brake unit normal?	Yes	Go to the next step.
		No	Replace power brake unit, then go to Step 8. (See POWER BRAKE UNIT REMOVAL/INSTALLATION [L.H.D.].) (See POWER BRAKE UNIT REMOVAL/INSTALLATION [R.H.D.].)
6	INSPECT POWER BRAKE UNIT VACUUM SENSOR •  Inspect the Power brake unit vacuum sensor operation. (See POWER BRAKE UNIT VACUUM SENSOR INSPECTION [SKYACTIV-D 2.2].) •  Is Power brake unit vacuum sensor normal?	Yes	Go to the next step.
		No	Replace Power brake unit vacuum sensor, then go to Step 8. (See POWER BRAKE UNIT VACUUM SENSOR REMOVAL/INSTALLATION.)
3	INSPECT OIL PRESSURE •  Inspect oil pressure. (See OIL PRESSURE INSPECTION [SKYACTIV-D 2.2].) •  Is oil pressure normal?	Yes	Go to the next step.
		No	Repair or replace the malfunctioning part Go to the next step.
8	INSPECT VACUUM PUMP •  Perform the vacuum pump on-vehicle inspection. (See VACUUM PUMP INSPECTION.) •  Has DTC P258B:00 been recorded?	Yes	Replace the vacuum pump, then go to the next step. (See VACUUM PUMP REMOVAL/INSTALLATION [SKYACTIV-D 2.2].)
		No	Repeat the inspection from Step 1. •  If the malfunction recurs, replace the PCM, then go to the next step. (See PCM REMOVAL/INSTALLATION [SKYACTIV-D 2.2].)
9	VERIFY OTHER DTCs •  Has any other DTC or pending code been stored?	Yes	Repair the malfunctioning location according to the applicable DTC troubleshooting. (See DTC TABLE [SKYACTIV-D 2.2].)
		No	DTC troubleshooting completed.