Illumination Circuit

NAVIGATION: NAVIGATION SYSTEM: Illumination Circuit
- Illumination Circuit

DESCRIPTION

Power is supplied to the radio and display receiver assembly and steering pad switch assembly illumination when the light control switch is in the TAIL or HEAD position.

WIRING DIAGRAM





INSPECTION PROCEDURE

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 precautionary notice for the Supplemental Restraint System Service Precautions.
* Inspect the fuses for circuits related to this system before performing the following inspection procedure.

PROCEDURE

1. CHECK ILLUMINATION

(a) Check if the illumination for the radio and display receiver assembly, steering pad switch, heater control switch or others (hazard switch, transmission control switch, etc.) comes on when the light control switch is turned to the TAIL or HEAD position.

Result





B -- CHECK HARNESS AND CONNECTOR (RADIO AND DISPLAY RECEIVER ASSEMBLY - BATTERY)

C -- CHECK HARNESS AND CONNECTOR (RADIO AND DISPLAY RECEIVER ASSEMBLY - LIGHT CONTROL RHEOSTAT)
A -- Continue to next step.

2. CHECK HARNESS AND CONNECTOR (SPIRAL CABLE SUB-ASSEMBLY - BATTERY)

(a) Disconnect the S8 spiral cable sub-assembly connector.





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

Standard Voltage:





Text in Illustration





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

3. INSPECT STEERING PAD SWITCH ASSEMBLY

(a) Disconnect the z1 steering pad switch assembly connector.

(b) Disconnect the S8 spiral cable sub-assembly connector.





Text in Illustration





(c) Connect the battery positive (+) lead to terminal IL+2 and the negative (-) lead to terminal EAU of the steering pad switch assembly connector.

(d) Check if the illumination for the steering pad switch assembly comes on.

OK:

Illumination for the steering pad switch assembly comes on.

NG -- REPLACE STEERING PAD SWITCH ASSEMBLY Removal
OK -- Continue to next step.

4. INSPECT SPIRAL CABLE SUB-ASSEMBLY

(a) Disconnect the z1 steering pad switch assembly connector.





(b) Disconnect the S8 spiral cable sub-assembly connector.

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

Standard Resistance:





Text in Illustration





NOTICE:
The spiral cable sub-assembly is an important part of the SRS airbag system. Incorrect removal or installation of the spiral cable sub-assembly may prevent the airbag from deploying. Be sure to read the pages shown in the brackets.

HINT
* Removal Removal
* Installation Installation

NG -- REPLACE SPIRAL CABLE SUB-ASSEMBLY Removal
OK -- Continue to next step.

5. CHECK HARNESS AND CONNECTOR (RADIO AND DISPLAY RECEIVER ASSEMBLY - SPIRAL CABLE SUB-ASSEMBLY)

(a) Disconnect the R15 radio and display receiver assembly connector.

(b) Disconnect the S8 spiral cable sub-assembly connector.

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

Standard Resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Problem Symptoms Table

6. CHECK HARNESS AND CONNECTOR (RADIO AND DISPLAY RECEIVER ASSEMBLY - BATTERY)

(a) Disconnect the R16 radio and display receiver assembly connector.





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

Standard Voltage:





Text in Illustration





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

7. CHECK HARNESS AND CONNECTOR (RADIO AND DISPLAY RECEIVER ASSEMBLY - LIGHT CONTROL RHEOSTAT)

(a) Disconnect the R16 radio and display receiver assembly connector.

(b) Disconnect the R4 light control rheostat connector.

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

Standard Resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Problem Symptoms Table