P0550

P0550 PSP Sensor

Component Description

Power steering pressure (PSP) sensor is installed to the power steering high-pressure tube and detects a power steering load. This sensor is a potentiometer which transforms the power steering load into output voltage, and emits the voltage signal to the ECM. The ECM controls the electric throttle control actuator and adjusts the throttle valve opening angle to increase the engine speed and adjusts the idle speed for the increased load.





On Board Diagnosis Logic

The MIL will not illuminate for this diagnosis.

NOTE:

If DTC P0550 is displayed with DTC P0643, first perform the trouble diagnosis for DTC P0643. Refer to [Power Supply and Ground Circuit Check] P0643.






DTC Confirmation Procedure

1) If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next step.
a) Turn ignition switch OFF and wait at least 10 seconds.
b) Turn ignition switch ON.
c) Turn ignition switch OFF and wait at least 10 seconds.
2) Start engine and let it idle for at least 5 seconds.
3) Check 1st trip DTC.
4) If 1st trip DTC is detected, go to "Diagnosis Procedure".

Diagnosis Procedure

1. CHECK GROUND CONNECTIONS

1 Turn ignition switch OFF.
2 Loosen and retighten three ground screws on the body. Refer to Power Supply and Ground Circuit Check.






OK or NG
OK
GO TO 2.
NG
Repair or replace ground connections.

2. CHECK PSP SENSOR POWER SUPPLY CIRCUIT

1 Disconnect power steering pressure (PSP) sensor harness connector.





2 Turn ignition switch ON.
3 Check voltage between PSP sensor terminal 3 and ground with SDT or tester.











OK or NG
OK
GO TO 3.
NG
Repair open circuit or short to ground or short to power in harness or connectors.

3. CHECK PSP SENSOR GROUND CIRCUIT FOR OPEN AND SHORT

1 Turn ignition switch OFF.
2 Disconnect ECM harness connector.
3 Check harness continuity between PSP sensor terminal 1 and ECM terminal 67.
Refer to Wiring Diagram.






4 Also check harness for short to ground and short to power.

OK or NG
OK
GO TO 4.
NG
Repair open circuit or short to ground or short to power in harness or connectors.

4. CHECK PSP SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT

1 Check harness continuity between ECM terminal 12 and PSP sensor terminal 2.






2 Also check harness for short to ground and short to power.

OK or NG
OK
GO TO 5.
NG
Repair open circuit or short to ground or short to power in harness or connectors.

5. CHECK PSP SENSOR

Refer to "Component Inspection".

OK or NG
OK
GO TO 6.
NG
Replace PSP sensor. Refer to [Hydraulic Line: Removal and Installation] Service and Repair.

6. CHECK INTERMITTENT INCIDENT

Refer to [Service Information for Electrical Incident: Intermittent Incident] Service Information for Electrical Incident: Intermittent Incident.


INSPECTION END

Component Inspection

Power Steering Pressure Sensor

1) Reconnect all harness connectors disconnected.
2) Start engine and let it idle.
3) Check voltage between ECM terminal 12 and ground under the following conditions.