AIR CONDITIONING SYSTEM Steering Pad Switch Circuit

DESCRIPTION

The R/F, TEMP UP (+), and TEMP DOWN (-) switches are located on the steering pad switch RH. The resistance of the steering pad switch RH changes in accordance with switch operation. The A/C control assembly outputs voltage to the steering pad switch RH and reads voltage changes due to the resistance changes that result from switch operation.

Tech Tips

If there is an open in the circuit, the A/C system cannot be operated by the steering pad switch RH.

If there is a short in the circuit, the resulting condition is the same as if the switch were continuously depressed. Therefore, the A/C control assembly cannot be operated by the steering pad switch RH, and the A/C control assembly will not be able to function correctly.

WIRING DIAGRAM

A01JASBE05

INSPECTION PROCEDURE

Note

The vehicle is equipped with a SRS (Supplemental Restraint System). Before servicing (including removal or installation of parts), be sure to read the precaution for Supplemental Restraint System Click here.

PROCEDURE


  1. INSPECT A/C CONTROL ASSEMBLY


    1. A01J8FKE32
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Spiral with Sensor Cable Sub-assembly)

      Disconnect the connector from the spiral with sensor cable sub-assembly.

    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition
      L52-10 (AC1) - Body ground Power switch off Below 1 V
      L52-10 (AC1) - Body ground Power switch on (IG) 4.5 to 5.5 V

    NG

    CHECK HARNESS AND CONNECTOR (A/C CONTROL ASSEMBLY - SPIRAL WITH SENSOR CABLE SUB-ASSEMBLY) Click here

    OK

  2. CHECK HARNESS AND CONNECTOR


    1. Disconnect the connector from the navigation receiver assembly.

    2. Disconnect the connector from the radio and display receiver assembly.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      L149-23 (SWG) - L52-4 (EAU)*1 Always Below 1 Ω
      L130-23 (SWG) - L52-4 (EAU)*2 Always Below 1 Ω
      L126-6 (SWG) - L52-4 (EAU)*3 Always Below 1 Ω
      L52-4 (EAU) - Body ground*3 Always Below 1 Ω
      L149-23 (SWG) - Body ground*1 Always 10 kΩ or higher
      L130-23 (SWG) - Body ground*2 Always 10 kΩ or higher
      L126-6 (SWG) - Body ground*3 Always 10 kΩ or higher

      • *1: for Radio and Display Receiver Type

      • *2: for Navigation Receiver Type

      • *3: except Radio and Display Receiver Type and Navigation Receiver Type


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. INSPECT STEERING PAD SWITCH RH


    1. Disconnect the connector from the steering pad switch RH.

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

      A01J9GTE01
      Standard Resistance
      Tester Connection Condition Specified Condition
      z9-3 (AC1) - z9-8 (EAU) No switch pushed 95 to 105 kΩ
      z9-3 (AC1) - z9-8 (EAU) R/F switch pushed 323 to 335 Ω
      z9-3 (AC1) - z9-8 (EAU) TEMP+ switch pushed 980 to 1020 Ω
      z9-3 (AC1) - z9-8 (EAU) TEMP- switch pushed 3048 to 3172 Ω
      Text in Illustration
      *1

      Component without harness connected

      (Steering Pad Switch RH)

      		 *2 TEMP+ Switch
      *3 TEMP- Switch *4 R/F Switch

    NG

    REPLACE STEERING PAD SWITCH RH Click here

    OK

  4. INSPECT SPIRAL WITH SENSOR CABLE SUB-ASSEMBLY


    1. A01J99CE06
      Text in Illustration
      *1

      Component without harness connected

      (Spiral with Sensor Cable Sub-assembly)
      *2 Steering Pad Switch Side
      *3 Vehicle Side

      Disconnect the connector from the spiral with sensor cable sub-assembly.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      L52-10 (AC1) - z9-3 (AC1) Center Below 1 Ω
      2.5 rotations to the left
      2.5 rotations to the right
      L52-4 (EAU) - z9-8 (EAU) Center Below 1 Ω
      2.5 rotations to the left
      2.5 rotations to the right

      Note

      The spiral with sensor cable sub-assembly is an important part of the SRS airbag system. Incorrect removal or installation of the spiral with sensor cable sub-assembly may prevent the airbag from deploying. Refer to the pages shown in the brackets.

      Tech Tips


      • Removal Click here

      • Installation Click here

      • The spiral cable makes a maximum of approximately 5 rotations.


    NG

    REPLACE SPIRAL WITH SENSOR CABLE SUB-ASSEMBLY Click here

    OK

  5. CONFIRM MODEL

    Result
    Result Proceed to
    w/ Navigation Receiver Assembly A
    w/ Radio and Display Receiver Assembly B

    B

    REPLACE RADIO AND DISPLAY RECEIVER ASSEMBLY Click here

    C

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Click here

    A

  6. REPLACE NAVIGATION RECEIVER ASSEMBLY


    1. Replace the navigation receiver assembly with a known good one and check if the same problem occurs again Click here.

      OK
      Same problem does not occur.

    NG

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Click here

    OK

    END (NAVIGATION RECEIVER ASSEMBLY WAS DEFECTIVE)

  7. REPLACE RADIO AND DISPLAY RECEIVER ASSEMBLY


    1. Replace the radio and display receiver assembly with a known good one and check if the same problem occurs again Click here.

      OK
      Same problem does not occur.

    NG

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Click here

    OK

    END (RADIO AND DISPLAY RECEIVER ASSEMBLY WAS DEFECTIVE)

  8. CHECK HARNESS AND CONNECTOR (A/C CONTROL ASSEMBLY - SPIRAL WITH SENSOR CABLE SUB-ASSEMBLY)


    1. A01JCTNE30

      Disconnect the connector from the A/C control assembly.

    2. A01J8FKE35
      Text in Illustration
      *1

      Front view of wire harness connector

      (to A/C Control Assembly)
      *2

      Front view of wire harness connector

      (to Spiral with Sensor Cable Sub-assembly)

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      L20-3 (SWO) - L52-10 (AC1) Always Below 1 Ω
      L20-3 (SWO) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE A/C CONTROL ASSEMBLY Click here