Dtc P0550 Power Steering Pressure Sensor Circuit


DESCRIPTION

WIRING DIAGRAM

MONITOR DESCRIPTION

INSPECTION PROCEDURE

CHECK HARNESS AND CONNECTOR (ECM - POWER STEERING OIL PRESSURE SWITCH)

REPLACE POWER STEERING OIL PRESSURE SWITCH

CONFIRM WHETHER DTC OUTPUT RECURS

DTC P0550 Power Steering Pressure Sensor Circuit

DTC P0552 Power Steering Pressure Sensor Circuit Low Input

DTC P0553 Power Steering Pressure Sensor Circuit High Input


DESCRIPTION

The power steering oil pressure switch is turned on when a power steering wheel load is generated by turning the steering wheel. The ECM regulates the engine idling speed according to the voltage output of the sensor.

DTC No.
DTC Detection Condition
Trouble Area
P0550
Power steering oil pressure switch voltage below 0.28 V, or higher than 4.9 V for 0.5 seconds while engine running (1 trip detection logic).
  1. Open or short in power steering oil pressure switch circuit
  2. Power steering oil pressure switch
  3. ECM
P0552
Power steering oil pressure switch voltage below 0.28 V for 0.5 seconds while engine running (1 trip detection logic).
  1. Open or short in power steering oil pressure switch circuit
  2. Power steering oil pressure switch
  3. ECM
P0553
Power steering oil pressure switch voltage higher than 4.9 V for 0.5 seconds while engine running (1 trip detection logic).
  1. Open or short in power steering oil pressure switch circuit
  2. Power steering oil pressure switch
  3. ECM

WIRING DIAGRAM

  1. for Automatic Transmission

Land Cruiser, Land Cruiser Prado. Grj150 Trj150,155 Kdj150,155 Lj150, Gdj150,155.1Gr-Fe Engine Control.Sfi System.
Dtc
  P0550  Power Steering Pressure Sensor Circuit

  1. for Manual Transmission

Land Cruiser, Land Cruiser Prado. Grj150 Trj150,155 Kdj150,155 Lj150, Gdj150,155.1Gr-Fe Engine Control.Sfi System.
Dtc
  P0550  Power Steering Pressure Sensor Circuit


MONITOR DESCRIPTION

The ECM monitors the sensor voltage and uses this value to regulate the engine idling speed. When the sensor output voltage deviates from the normal operating range, the ECM determines that there is a malfunction in the power steering oil pressure switch and stores a DTC.

INSPECTION PROCEDURE

HINT:
  1. If other DTCs relating to different systems that have terminal ETHW as the ground terminal are output simultaneously, terminal ETHW may have an open circuit.
  2. Read freeze frame data using the GTS. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.
1.CHECK HARNESS AND CONNECTOR (ECM - POWER STEERING OIL PRESSURE SWITCH)
  1. Disconnect the power steering oil pressure switch connector.

  1. Disconnect the ECM connector.

  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance:
    for Automatic Transmission
    Tester Connection
    Condition
    Specified Condition
    C29-2 (PSP) - C36-17 (PSP)
    Always
    Below 1 Ω
    C29-1 (VC) - C34-6 (VCV2)
    Always
    Below 1 Ω
    C29-3 (E2) - C36-4 (ETHW)
    Always
    Below 1 Ω
    C29-2 (PSP) or C36-17 (PSP) - Body ground
    Always
    10 kΩ or higher
    C29-1 (VC) or C34-6 (VCV2) - Body ground
    Always
    10 kΩ or higher
    for Manual Transmission
    Tester Connection
    Condition
    Specified Condition
    C29-2 (PSP) - C35-16 (PSP)
    Always
    Below 1 Ω
    C29-1 (VC) - C34-16 (VCV2)
    Always
    Below 1 Ω
    C29-3 (E2) - C35-8 (ETHW)
    Always
    Below 1 Ω
    C29-2 (PSP) or C35-16 (PSP) - Body ground
    Always
    10 kΩ or higher
    C29-1 (VC) or C34-16 (VCV2) - Body ground
    Always
    10 kΩ or higher
  1. Reconnect the power steering oil pressure switch connector.

  1. Reconnect the ECM connector.



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


2.REPLACE POWER STEERING OIL PRESSURE SWITCH
  1. Replace the power steering oil pressure switch (LandCruiser RM000003BJ401VX.html).


NEXT


3.CONFIRM WHETHER DTC OUTPUT RECURS
  1. Connect the GTS to the DLC3.

  1. Turn the engine switch on (IG).

  1. Turn the GTS on.

  1. Start the engine.

  1. Idle the engine for 5 seconds.

  1. Read the DTCs.

    Result
    Result
    Proceed to
    P0550, P0552 and/or P0553 is output
    A
    No DTC is output
    B


B
END
A

REPLACE ECM (LandCruiser RM00000329203TX.html)