Inspection Procedure

WARNING: This page is about a different car, the 2007 Lexus GX 470. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: The vehicle is equipped with an SRS (Supplemental Restraint System) which includes components such as airbags. Before servicing (including removal or installation of parts), be sure to read the PRECAUTION in the Supplemental Restraint System article.

CHECK HARNESS AND CONNECTOR (RADIO RECEIVER - SPIRAL CABLE)

Fig 1: Identifying Harness & Connector (Radio Receiver - Spiral Cable)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Disconnect the R2 receiver connector.
Disconnect the C13 cable connector.

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

Standard resistance

RADIO RECEIVER - SPIRAL CABLE

Tester Connection	Condition	Specified Condition
R2-6 (SWGND) - C13-10 (EAU)	Always	Below 1 Ω
R2-8 (STSW2) - C13-10 (AU2)	Always	Below 1 Ω
R2-6 (SWGND) - Body ground	Always	10 kΩ or higher
R2-8 (STSW2) - Body ground	Always	10 kΩ or higher

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: Go to Next Step

INSPECT SPIRAL CABLE

Disconnect the C13 and A cable connectors.

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

Standard resistance

SPIRAL CABLE

Tester Connection	Spiral Cable Position	Specified Condition
C13-10 (EAU) - A-10 (EAU)	Center	Below 1 Ω
	2.5 rotations to the left
	2.5 rotations to the right
C13-11 (AU2) - A-11 (AU2)	Center	Below 1 Ω
	2.5 rotations to the left
	2.5 rotations to the right

NOTE: The spiral cable is an important part of the SRS airbag system. Incorrect removal or installation of the spiral cable may prevent the airbag from deploying. Be sure to read the PRECAUTION for the supplemental restraint system article.

Fig 2: Identifying Spiral Cable

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: REPLACE SPIRAL CABLE SUB-ASSEMBLY

OK: Go to Next Step

INSPECT STEERING PAD SWITCH ASSEMBLY

Disconnect the A switch connector.

Fig 3: Inspecting Steering Pad Switch Assembly
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

Standard resistance

STEERING PAD SWITCH ASSEMBLY

Tester Connection	Switch Condition	Specified Condition
A-11 (AU2) - A-10 (EAU)	No switch is pushed	Approx. 100 kΩ
A-11 (AU2) - A-10 (EAU)	VOICE switch: push	Approx. 3.2 kΩ
A-11 (AU2) - A-10 (EAU)	ON HOOK switch: push	Approx. 0.33 kΩ
A-11 (AU2) - A-10 (EAU)	OFF HOOK switch: push	Approx. 1.0 kΩ

OK: PROCEED TO NEXT INSPECTION PROCEDURE SHOWN IN PROBLEM SYMPTOMS TABLE

NG: Go to Next Step

INSPECT STEERING PAD SWITCH CABLE

Fig 4: Identifying Steering Pad Switch Cable

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Disconnect the steering pad switch LH and the steering pad switch RH.

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

Standard resistance

STEERING PAD SWITCH CABLE

Tester Connection	Condition	Specified Condition
B-1 - C-1	Always	Below 1 Ω
B-2 - C-2	Always	Below 1 Ω
B-3 - C-3	Always	Below 1 Ω
B-4 - C-4	Always	Below 1 Ω
B-5 - C-5	Always	Below 1 Ω
B-6 - C-6	Always	Below 1 Ω
B-7 - C-7	Always	Below 1 Ω
B-8 - C-8	Always	Below 1 Ω
B-1 - Body ground	Always	10 kΩ or higher
B-2 - Body ground	Always	10 kΩ or higher
B-3 - Body ground	Always	10 kΩ or higher
B-4 - Body ground	Always	10 kΩ or higher
B-5 - Body ground	Always	10 kΩ or higher
B-6 - Body ground	Always	10 kΩ or higher
B-7 - Body ground	Always	10 kΩ or higher
B-8 - Body ground	Always	10 kΩ or higher

NG: REPLACE STEERING PAD SWITCH CABLE

OK: Go to Next Step

INSPECT STEERING PAD SWITCH RH

Fig 5: Identifying Steering Pad Switch RH

Reconnect the steering pad switch RH.

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

Standard resistance

STEERING PAD SWITCH RH

Tester Connection	Switch Condition	Specified Condition
B-4 (AU2) - B-2 (EAU)	No switch is pushed	10 kΩ or higher
B-5 (AU2) - B-3 (EAU)
B-5 (AU2) - B-2 (EAU)
B-4 (AU2) - B-3 (EAU)
B-4 (AU2) - B-2 (EAU)	VOICE switch: push	Approx. 3.2 kΩ
B-5 (AU2) - B-3 (EAU)
B-5 (AU2) - B-2 (EAU)
B-4 (AU2) - B-3 (EAU)
B-4 (AU2) - B-2 (EAU)	ON HOOK switch: push	Approx. 0.33 kΩ
B-5 (AU2) - B-3 (EAU)
B-5 (AU2) - B-2 (EAU)
B-4 (AU2) - B-3 (EAU)
B-4 (AU2) - B-2 (EAU)	OFF HOOK switch: push	Approx. 1.0 kΩ
B-5 (AU2) - B-3 (EAU)
B-5 (AU2) - B-2 (EAU)
B-4 (AU2) - B-3 (EAU)

NG: REPLACE STEERING PAD SWITCH RH

OK: REPLACE STEERING PAD SWITCH LH