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Mitsubishi Montero Sport (2004+). Manual - part 315

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

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MULTIPORT FUEL INJECTION (MFI)

13A-673

DTC P0554: Power Steering Pressure Sensor Circuit Intermittent

CIRCUIT OPERATION

• A battery positive voltage is applied to the power

steering pressure switch output terminal (terminal
No. 1) from the PCM (terminal No. 52) via the
resistor in the PCM.

TECHNICAL DESCRIPTION

• The power steering pressure switch converts the

existence of a power steering load into a high/low
voltage, and inputs it into the PCM.

• When the steering wheel is turned, hydraulic

pressure rises. The power steering pressure
switch closes, and the applied battery positive
voltage will be grounded. With this, the power
steering pressure switch output voltage will fluc-
tuate between 12 volts and 0 volt.

• While driving with the steering wheel held

straight, the power steering pressure switch turns
"OFF".

• The PCM checks whether the power steering

pressure switch turns "OFF" or "ON" during driv-
ing.

DESCRIPTIONS OF MONITOR METHODS
Power steering pressure switch stays on during

specified go/stop operations.

MONITOR EXECUTION
Continuous

AK000604

Power Steering Pressure Switch Circuit

UE-

WHITE

POWER STEERING
PRESSURE SWITCH

POWERTRAIN CONTROL
MODULE (PCM)

A-76

42 43

48 49 50 51 52 53 54 55 56 57

60 61 62 63

64 65 66

C-90
(MU803781)

AK200032 AB

CONNECTOR: A-76

POWER STEERING
PRESSURE SWITCH

A-76

AK103738AC

CONNECTOR: C-90

PCM

C-90(GR)

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

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MULTIPORT FUEL INJECTION (MFI)

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MONITOR EXECUTION CONDITIONS (Other
monitor and Sensor)

Other Monitor (There is no temporary DTC stored

in memory for the item monitored below)

• Not applicable

Sensor (The sensor below is determined to be

normal)

• Engine coolant temperature sensor

LOGIC FLOW CHART

Check Conditions

• Engine coolant temperature is higher than 30°C

(86

°F).

• Vehicle speed is higher than 50 km/h (31 mph).

Judgment Criteria

• The ON/OFF frequency of a power steering pres-

sure switch is 10 Hz or more for 20 seconds.

OBD-II DRIVE CYCLE PATTERN
None.

TROUBLESHOOTING HINTS (The most likely
causes for this code to be set are: )

• Power steering pressure switch failed.

• Air entered to power steering system.

• Open or shorted power steering pressure switch

circuit, harness damage or connector damage.

• PCM failed.

START

END

YES

MALFUNCTION

GOOD

CONTINUOUS FAILURE

FOR 20secs

FREQUENCY > 10Hz

MONITORING

CONDITIONS

AK301790

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

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MULTIPORT FUEL INJECTION (MFI)

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DIAGNOSIS

Required Special Tools:

• MB991958: Scan Tool (MUT-III Sub Assembly)

• MB991824: V.C.I

• MB991827: USB Cable

• MB991911: Main Harness B

STEP 1. Using scan tool MB991958, check data list item 27:
Power Steering Pressure Switch.

CAUTION

To prevent damage to scan tool MB991958, always turn the
ignition switch to the "LOCK" (OFF) position before con-
necting or disconnecting scan tool MB991958.
(1) Connect scan tool MB991958 to the data link connector.
(2) Start the engine and run at idle.
(3) Set scan tool MB991958 to the data reading mode for item

27, Power Steering Pressure Switch.

• If the steering wheel is stopped while idling, "OFF" will

be displayed.

• If the steering wheel is steered while idling, "ON" will be

displayed.

(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the sensor operating properly?

YES : It can be assumed that this malfunction is intermittent.

Refer to GROUP 00, How to Use
Troubleshooting/Inspection Service Points

P.00-7

NO : Go to Step 2.

STEP 2. Check the power steering fluid level.
Refer to GROUP 37A, On-Vehicle Service - Fluid Level Check

P.37A-19

Q: Are there any abnormalities?

YES : Go to Step 3.
NO : Repair it. Then go to Step 7.

STEP 3. Check the power steering pressure switch.
Refer to GROUP 37A, On-Vehicle Service - Power Steering
Pressure Switch Check

P.37A-21

Q: Are there any abnormalities?

YES : Go to Step 4.
NO : Replace the power steering pressure switch. Then go

to Step 7.

AK303629AB

MB991911

MB991827

MB991824

16-PIN

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

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STEP 4. Check the oil pump pressure .
Refer to GROUP 37A, On-Vehicle Service - Oil Pump Pressure
Test

P.37A-4

Q: Are there any abnormalities?

YES : Go to Step 5.
NO : Repair it. Then go to Step 7.

STEP 5. Check connector A-76 at the power steering
pressure switch and connector C-90 at PCM for damage.
Q: Is the connector in good condition?

YES : Go to Step 6.
NO : Repair or replace it. Refer to GROUP 00E, Harness

Connector Inspection

P.00E-2

. Then go to Step 7.

AK200031

CONNECTOR: A-76

A-76

HARNESS CONNECTOR:
COMPONENT SIDE

AK103762

46 45 44

CONNECTOR: C-90

C-90(GR)

HARNESS CONNECTOR:
COMPONENT SIDE

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