DESCRIPTION
This circuit sends an operation signal from the steering pad switch assembly to the radio receiver 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 radio receiver assembly cannot be operated using the steering pad switch assembly, and the radio receiver assembly itself will not function.
WIRING DIAGRAM
 CAUTION / NOTICE / HINT
NOTICE:
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.
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PROCEDURE
|   1.  |    INSPECT STEERING PAD SWITCH ASSEMBLY  |  
(a) Remove the steering pad switch assembly.
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(b) Inspect the steering pad switch assembly.
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| NG |     |    REPLACE STEERING PAD SWITCH ASSEMBLY  |  
 
  |  
|   2.  |    INSPECT SPIRAL CABLE SUB-ASSEMBLY  |  
(a) Remove the spiral cable sub-assembly.
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(b) Inspect the spiral cable sub-assembly.
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| NG |     |    REPLACE SPIRAL CABLE SUB-ASSEMBLY  |  
 
  |  
|   3.  |    CHECK HARNESS AND CONNECTOR (STEERING PAD SWITCH SIGNAL)  |  
(a) Disconnect the J148 radio receiver assembly connector.
(b) Disconnect the J29 spiral cable sub-assembly connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
|   Tester Connection  |    Condition  |    Specified Condition  |  
|---|---|---|
|   J148-21 (SW1) - J29-6 (AU1)  |    Always  |    Below 1 Ω  |  
|   J148-22 (SW2) - J29-5 (AU2)  |    Always  |    Below 1 Ω  |  
|   J148-24 (SWG) - J29-3 (EAU)  |    Always  |    Below 1 Ω  |  
|   J148-21 (SW1) or J29-6 (AU1) - Body ground  |    Always  |    10 kΩ or higher  |  
|   J148-22 (SW2) or J29-5 (AU2) - Body ground  |    Always  |    10 kΩ or higher  |  
|   J148-24 (SWG) or J29-3 (EAU) - Body ground  |    Always  |    10 kΩ or higher  |  
| OK |     |    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE  |  
| NG |     |    REPAIR OR REPLACE HARNESS OR CONNECTOR (RADIO RECEIVER ASSEMBLY - SPIRAL CABLE SUB-ASSEMBLY)  |  
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