Inspection Procedure

1. Remove the E/G RM-IG1-1 fuse from the engine room No. 2 relay block.
2. Measure the resistance of the fuse.

   Standard resistance 

   FUSE (E/G RM-IG1-1)
   
   

   Tester Connection	Condition	Specified Condition
   E/G RM-IG1-1 fuse	Always	Below 1 Ω

NG: REPLACE FUSE 

1. Start the engine.
2. Check the indication condition of the PS warning light by wiggling the power steering ECU connector and wire harness up and down, and right and left.

   OK : 

   PS warning light indication condition does not change. 

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: GO TO NEXT STEP 

1. Using the intelligent tester or Techstream, check for DTCs and confirm that there are no problems in the CAN communication system (see DIAGNOSIS SYSTEM ).

   Result 

   CAN COMMUNICATION SYSTEM
   
   

   DTC Condition	Proceed to
   DTC is not output	A
   DTC is output	B

B: GO TO CAN COMMUNICATION SYSTEM  (See HOW TO PROCEED WITH TROUBLESHOOTING )

A: GO TO NEXT STEP 

1. Using the intelligent tester or Techstream, check for DTCs and confirm that there are no problems in the brake control system.

   Result 

   BRAKE CONTROL SYSTEM
   
   

   DTC Condition	Proceed to
   DTC is not output	A
   DTC is output	B

B: GO TO BRAKE CONTROL SYSTEM  (See HOW TO PROCEED WITH TROUBLESHOOTING )

A: GO TO NEXT STEP 

1. Disconnect the A44 ECU connector.
2. Measure the voltage according to the value(s) in the table below.

   Standard voltage 

   POWER STEERING ECU - BODY GROUND VOLTAGE
   
   

   Tester Connection	Switch Condition	Specified Condition
   A44-9 (IG) - Body ground	Engine switch on (IG)	11 to 14 V

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

   Standard resistance 

   POWER STEERING ECU - BODY GROUND RESISTANCE
   
   

   Tester Connection	Condition	Specified Condition
   A44-5 (PGND) - Body ground	Always	Below 1 Ω

   Fig 1: Checking Harness And Connector (Power Steering ECU - Body Ground)

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: GO TO NEXT STEP 

1. Replace the power steering ECU (see REMOVAL  ).
2. After replacing the power steering ECU, check the illumination condition of the combination meter's PS warning light.

   OK : 

   Engine switch turned on (IG), illuminated → engine started, turns off. 

   NOTE: If replacing the power steering ECU, initialize the rotation angle sensor value and calibrate the torque sensor zero point (see CALIBRATION  ).

NG: REPLACE COMBINATION METER ASSEMBLY  (See REMOVAL )

OK: END