Illumination Circuit (To 8/2009): Procedure

1. Check if the illumination for the radio receiver assembly, steering pad switch assembly, heater control switch or others (hazard switch, transmission control switch, etc.) comes on when the light control switch is turned to the head or tail position.

   Result

   Result	Proceed to
   Illumination comes on for all components except steering pad switch assembly.	A
   Illumination comes on for all components except radio receiver assembly.	B
   No illumination comes on (radio receiver assembly, hazard switch, heater control switch, etc.).	C
   Illumination comes on only for steering pad switch assembly.	D

D → See step   10 

C → See step   9 

B → See step   7 

A: Go to next step 

1. Disconnect the spiral with sensor cable sub-assembly connector.
   Fig 1: Identifying F40 Connector

   Courtesy 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
   F40-12 (IL+2) - Body ground	Light control switch tail or head	11 to 14 V

   TEXT IN ILLUSTRATION
   
   

   *1	Front view of wire harness connector (to Spiral with Sensor Cable Sub-assembly)

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to next step 

1. Disconnect the steering pad switch assembly connector.
2. Connect a battery positive (+) lead to terminal IL+2 and a negative (-) lead to terminal EAU of the steering pad switch assembly connector.
   Fig 2: Identifying z5 Connector

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
3. Check if the illumination for the steering pad switch assembly comes on.

   OK

   Illumination for the steering pad switch assembly comes on.

   TEXT IN ILLUSTRATION
   
   

   *1

   Front view of wire harness connected (Steering Pad Switch Assembly)

   -

   -

NG → See step   11 

OK: Go to next step 

1. Disconnect the steering pad switch assembly and spiral with sensor cable sub-assembly connectors.
   Fig 3: Identifying Steering Pad Switch And Spiral With Sensor Cable Sub-Assembly Connector Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   z5-8 (EAU) - F40-4 (EAU)	Center	Below 1 Ω
   	2.5 rotations to the left
   	2.5 rotations to the right
   z5-5 (IL+2) - F40-12 (IL+2)	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. Be sure to read articles shown in the brackets.

   HINT: 

   • Removal. Refer to REMOVAL
   • Installation. Refer to INSTALLATION
   TEXT IN ILLUSTRATION
   
   

   *1	Steering Pad Switch Assembly Side
   *2	Vehicle Side

NG → See step   12 

OK: Go to next step 

1. Disconnect the radio receiver assembly and spiral with sensor cable sub-assembly connectors.
   Fig 4: Identifying G9 & F40 Connectors

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   G9-6 (SWG) - F40-4 (EAU)	Always	Below 1 Ω
   G9-6 (SWG) - Body ground	Always	10 kΩ or higher

   TEXT IN ILLUSTRATION
   
   

   *1	Front view of wire harness connector (to Radio Receiver Assembly)
   *2	Front view of wire harness connector (to Spiral with Sensor Cable Sub-assembly)

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK → See step   6 

1. Disconnect the radio receiver assembly connector.
   Fig 5: Identifying G7 Connector

   Courtesy 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
   G7-2 (ILL+) - Body ground	Light control switch tail or head	11 to 14 V

   TEXT IN ILLUSTRATION
   
   

   *1	Front view of wire harness connector (to Radio Receiver Assembly)

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to next step 

1. Disconnect the radio receiver assembly and combination meter assembly connectors.
   Fig 6: Identifying G7 & F15 Connectors

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   G7-12 (ILL-) - F15-15 (ILL-)	Always	Below 1 Ω
   F15-16 (E2) - Body ground	Always	Below 1 Ω
   F15-15 (ILL-) - Body ground	Always	10 kΩ or higher

   TEXT IN ILLUSTRATION
   
   

   *1	Front view of wire harness connector (to Radio Receiver Assembly)
   *2	Front view of wire harness connector (to Combination Meter Assembly)

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK → See step   6