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EPS Warning Light Circuit [08/2014 - ]: Procedure

  1. CHECK FOR DTC (CAN COMMUNICATION SYSTEM) 
    1. Check for DTCs. Refer to DIAGNOSIS SYSTEM [08/2014 - ] .

      OK

      DTC is not output.

    NG → See step   6 

    OK: Go to next step 

  2. CHECK HARNESS AND CONNECTOR (POWER STEERING ECU ASSEMBLY - BODY GROUND) 
    1. Disconnect the connectors from the power steering ECU assembly.
      GTY334302Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      L188-6 (IG) - Body ground Power switch on (IG) 9 to 16 V
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A27-2 (PGND) - Body ground Always Below 1 Ω
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to Power Steering ECU Assembly)

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  3. INSPECT COMBINATION METER 
    1. Reconnect the power steering ECU assembly connector.
    2. Perform the Active Test of the combination meter using the Techstream. Refer to DATA LIST / ACTIVE TEST [08/2014 - ] .
    3. Check the combination meter.

      OK

      The EPS warning light turns on or off in accordance with the Techstream operation.

      HINT: 

      If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step before replacing the part. Refer to PROBLEM SYMPTOMS TABLE [08/2014 - ] .

    NG → See step   4 

    OK → See step   5 

  4. REPLACE METER CIRCUIT PLATE NO. 3. Refer to  REMOVAL [08/2014 - ] 
  5. REPLACE POWER STEERING ECU ASSEMBLY. Refer to  REMOVAL [08/2014 - ] 
  6. GO TO CAN COMMUNICATION SYSTEM. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [08/2014 - ]