Mitsubishi Montero (2002-2004). Manual — part 707

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DIAGNOSTIC TROUBLE CODE PROCEDURES

13Ac-525

STEP 10. Check for short circuit to ground between power
steering pressure switch connector B-29 (terminal No. 1)
and PCM connector D-133 (terminal No. 47).
Q: Is the harness wire in good condition?

YES : Replace the PCM. Then go to Step 14.
NO : Repair it. Then go to Step 14.

STEP 11. Replace the power steering pressure switch.
(1) Replace the power steering pressure switch.
(2) Check the trouble symptoms.
(3) Read in the diagnostic trouble code (DTC).
Q: Is DTC P0551 set?

YES : Go to Step 12.
NO : Go to Step 14.

AK200973

1

AB

CONNECTOR: B-29

B-29(B)

HARNESS
CONNECTOR:
COMPONENT SIDE

AK200939

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47

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52

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57

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50

51

AB

CONNECTOR: D-133

HARNESS CONNECTOR:
COMPONENT SIDE

PCM

D-133(GR)

AK200973

1

AB

CONNECTOR: B-29

B-29(B)

HARNESS
CONNECTOR:
COMPONENT SIDE

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DIAGNOSTIC TROUBLE CODE PROCEDURES

13Ac-526

STEP 12. Check harness connector D-133 at PCM for
damage.
Q: Is the harness connector in good condition?

YES : Go to Step 13.
NO : Repair or replace it. Refer to GROUP 00E, Harness

Connector Inspection

P.00E-2

. Then go to Step 14.

STEP 13. Check for harness damage between power
steering pressure switch connector B-29 (terminal No. 1)
and PCM connector D-133 (terminal No. 47).
Q: Is the harness wire in good condition?

YES : Replace the PCM. Then go to Step 14.
NO : Repair it. Then go to Step 14.

AK200939

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AB

CONNECTOR: D-133

HARNESS CONNECTOR:
COMPONENT SIDE

PCM

D-133(GR)

AK200973

1

AB

CONNECTOR: B-29

B-29(B)

HARNESS
CONNECTOR:
COMPONENT SIDE

AK200939

31

32

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AB

CONNECTOR: D-133

HARNESS CONNECTOR:
COMPONENT SIDE

PCM

D-133(GR)

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DIAGNOSTIC TROUBLE CODE PROCEDURES

13Ac-527

STEP 14. Using scan tool MB991502, check data list item
27: Power Steering Pressure Switch.

CAUTION

To prevent damage to scan tool MB991502, always turn the
ignition switch to the "LOCK" (OFF) position before con-
necting or disconnecting scan tool MB991502.
(1) Connect scan tool MB991502 to the data link connector.
(2) Start the engine and run at idle.
(3) Set scan tool MB991502 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 switch operating properly?

YES : The inspection is complete.
NO : Retry the troubleshooting.

DTC P0554: Power Steering Pressure Sensor Circuit Intermittent

ACX01539

16-PIN

MB991502

AC

AK201149

YELL

OW

POWERTRAIN
CONTROL
MODULE (PCM)

1

B-29

(MU801211)

POWER STEERING
PRESSURE SWITCH

47

1

Power Steering Pressure Switch Circuit

31

35363738394041 42 43
444546474849

50 51

5253

545556

57 58

32

33 34

D-133

(MU803803)

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DIAGNOSTIC TROUBLE CODE PROCEDURES

13Ac-528

.

CIRCUIT OPERATION

• A battery positive voltage is applied to the power

steering pressure switch output terminal (terminal
No. 1) from the PCM (terminal No. 47) 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.

.

DTC SET CONDITIONS

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.

.

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, or loose connector.

• PCM failed.

AK200972

POWER
STEERING
OIL PUMP

POWER STEERING
PRESSURE SWITCH

AB

B-29(B)

CONNECTOR: B-29

AK201038

CONNECTOR: D-133

AC

PCM

D-133(GR)