C1551

POWER ASSIST SYSTEMS: POWER STEERING SYSTEM (for 2AZ-FE): C1551: IG Power Supply Voltage Malfunction

DTC C1551 - IG Power Supply Voltage Malfunction

DESCRIPTION

The power steering ECU distinguishes the ignition switch status as on (IG) or off through the IG power source circuit.






WIRING DIAGRAM





INSPECTION PROCEDURE
NOTE: If the steering column assembly or power steering ECU has been replaced, perform the rotation angle sensor initialization and torque sensor zero point calibration Programming and Relearning.

PROCEDURE

1. READ VALUE USING TECHSTREAM (IG POWER SUPPLY)
(a) Turn the ignition switch off.
(b) Connect the Techstream to the DLC3.
(c) Turn the ignition switch on (IG).
(d) Turn the Techstream on.
(e) Enter the following menus: Chassis / EMPS / Data List.
(f) Select the item "IG power supply" in the Data List and read the value displayed on the Techstream.

EMPS





OK:
The normal condition value is displayed on the Techstream.
NG -- INSPECT FUSE (ECU-IG NO. 1)
OK -- CHECK INTERMITTENT PROBLEMS
2. INSPECT FUSE (ECU-IG NO. 1)
(a) Remove the ECU-IG No. 1 fuse from the instrument panel junction block.
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:






NG -- REPLACE FUSE
OK -- Continue to next step.
3. CHECK HARNESS AND CONNECTOR (BATTERY - POWER STEERING ECU)




(a) Disconnect the connectors from the power steering ECU.
(b) Measure the voltage according to the value(s) in the table below.
Standard Voltage:





(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- REPLACE POWER STEERING ECU