NAVIGATION SYSTEM (for Navigation Receiver Type) Steering Pad Switch Circuit

DESCRIPTION

This circuit sends an operation signal from the steering pad switch assembly to the navigation ECU sub-assembly.

If there is an open in the circuit, the audio system cannot be operated using the steering pad switch assembly.

If there is a short in the circuit, the same condition as when a switch is continuously depressed occurs.

Therefore, the navigation ECU sub-assembly cannot be operated using the steering pad switch assembly, and also the navigation ECU sub-assembly itself cannot function.

WIRING DIAGRAM

A01HNFYE44

INSPECTION PROCEDURE

Note

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

PROCEDURE


  1. CHECK HARNESS AND CONNECTOR (STEERING PAD SWITCH SIGNAL)


    1. Disconnect the navigation ECU sub-assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      I67-21 (SW1) - I67-23 (SWG) No switch pushed 95 to 105 kΩ
      Up switch pushed Below 2.5 Ω
      Down switch pushed 313 to 345 Ω
      Volume+ switch pushed 950 to 1050 Ω
      Volume- switch pushed 2955 to 3265 Ω
      I67-22 (SW2) - I67-23 (SWG) No switch pushed 95 to 105 kΩ
      MODE/HOLD switch pushed Below 2.5 Ω
      On hook switch pushed 313 to 345 Ω
      Off hook switch pushed 950 to 1050 Ω
      Voice switch pushed 2955 to 3265 Ω
      I67-24 (SW3) - I67-23 (SWG) No switch pushed 95 to 105 kΩ
      Enter switch pushed Below 2.5 Ω
      Back switch pushed 313 to 345 Ω
      Right switch pushed 950 to 1050 Ω
      Left switch pushed 2955 to 3265 Ω

    NG
    OK
  2. INSPECT STEERING PAD SWITCH ASSEMBLY


    1. Disconnect the steering pad switch assembly connector.

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

      A01HO36E01
      Standard Resistance
      Tester Connection Condition Specified Condition
      z3-11 (AU1) - z3-8 (EAU) No switch pushed 95 to 105 kΩ
      Up switch pushed Below 2.5 Ω
      Down switch pushed 313 to 345 Ω
      Volume+ switch pushed 950 to 1050 Ω
      Volume- switch pushed 2955 to 3265 Ω
      z3-10 (AU2) - z3-8 (EAU) No switch pushed 95 to 105 kΩ
      MODE/HOLD switch pushed Below 2.5 Ω
      On hook switch pushed 313 to 345 Ω
      Off hook switch pushed 950 to 1050 Ω
      Voice switch pushed 2955 to 3265 Ω
      z3-9 (AU3) - z3-8 (EAU) No switch pushed 95 to 105 kΩ
      Enter switch pushed Below 2.5 Ω
      Back switch pushed 313 to 345 Ω
      Right switch pushed 950 to 1050 Ω
      Left switch pushed 2955 to 3265 Ω
      Text in Illustration
      *a

      Component without harness connected

      (Steering Pad Switch Assembly)

      *b Volume+
      *c Volume- *d Back
      *e MODE/HOLD *f Up
      *g Down *h Left
      *i Right *j Enter
      *k Off hook *l On hook
      *m Voice - -

    NG
    OK
  3. INSPECT SPIRAL CABLE WITH SENSOR SUB-ASSEMBLY


    1. Disconnect the steering pad switch assembly connector.

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

    3. A01HMW1E04
      Text in Illustration
      *a

      Component without harness connected

      (Spiral Cable with Sensor Sub-assembly)

      *b Steering Pad Switch Assembly Side
      *c Vehicle Side

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      z3-8 (EAU) - I28-3 (EAU) Center 3 Ω or less
      2.5 rotations to the left
      2.5 rotations to the right
      z3-11 (AU1) - I28-6 (AU1) Center 3 Ω or less
      2.5 rotations to the left
      2.5 rotations to the right
      z3-10 (AU2) - I28-5 (AU2) Center 3 Ω or less
      2.5 rotations to the left
      2.5 rotations to the right
      z3-9 (AU3) - I28-4 (AU3) Center 3 Ω or less
      2.5 rotations to the left
      2.5 rotations to the right
    4. After setting the spiral cable with sensor sub-assembly to the center position, rotate the spiral cable with sensor sub-assembly 2.5 times clockwise. Then while rotating the spiral cable with sensor sub-assembly 5 times counterclockwise, measure the resistance as shown in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      z3-8 (EAU) - I28-3 (EAU) Always 3 Ω or less
      z3-11 (AU1) - I28-6 (AU1) Always 3 Ω or less
      z3-10 (AU2) - I28-5 (AU2) Always 3 Ω or less
      z3-9 (AU3) - I28-4 (AU3) Always 3 Ω or less

      Note


      • Press and hold the lock located in the center of the spiral cable with sensor sub-assembly to rotate the spiral cable with sensor sub-assembly.

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

      • As the spiral cable with sensor sub-assembly may break, do not rotate the spiral cable with sensor sub-assembly more than the specified amount.

      Tech Tips



    NG
    OK