Inspection Procedure

WARNING: This page is about a different car, the 2008 Lexus RX 350. 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 PRECAUTION .

INSPECT RADIO RECEIVER

Disconnect the radio receiver connector R4.

Fig 1: Identifying Radio Receiver R4 Connector Terminals
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

Standard resistance

TESTER CONNECTION SPECIFIED CONDITION REFERENCE TABLE

Tester connection	Condition	Specified condition
SW1 - SWG	No switch is pushed	Approx. 100 kΩ
SW1 - SWG	SEEK+ switch: push	Approx. 0 Ω
SW1 - SWG	SEEK- switch: push	Approx. 0.3 kΩ
SW1 - SWG	VOL+ switch: push	Approx. 1 kΩ
SW1 - SWG	VOL- switch: push	Approx. 3.1 kΩ
SW2 - SWG	No switch is pushed	Approx. 100 kΩ
SW2 - SWG	MODE switch: push	Approx. 0 Ω
SW2 - SWG	VOICE switch: push	Approx. 3.1 kΩ
SW2 - SWG	ON HOOK switch: push	Approx. 0.3 kΩ
SW2 - SWG	OFF HOOK switch: push	Approx. 1 kΩ

NG: Go to step 2

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

INSPECT STEERING PAD SWITCH ASSEMBLY

Disconnect the steering pad switch assembly connector A.

Fig 2: Identifying Steering Pad Switch Assembly Connector Terminals
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

Standard resistance

TESTER CONNECTION SPECIFIED CONDITION REFERENCE TABLE

Tester connection	Condition	Specified condition
AU1 - EAU	No switch is pushed	Approx. 100 kΩ
AU1 - EAU	SEEK+ switch: push	Approx. 0 Ω
AU1 - EAU	SEEK- switch: push	Approx. 0.3 kΩ
AU1 - EAU	VOL+ switch: push	Approx. 1 kΩ
AU1 - EAU	VOL- switch: push	Approx. 3.1 kΩ
AU2 - EAU	No switch is pushed	Approx. 100 kΩ
AU2 - EAU	MODE switch: push	Approx. 0 Ω
AU2 - EAU	VOICE switch: push	Approx. 3.1 kΩ
AU2 - EAU	ON HOOK switch: push	Approx. 0.3 kΩ
AU2 - EAU	OFF HOOK switch: push	Approx. 1 kΩ

NG: REPLACE STEERING PAD SWITCH ASSEMBLY

OK: Go to Next Step

INSPECT SPIRAL CABLE

Disconnect the steering pad switch assembly and spiral cable connectors.

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

Standard resistance

TESTER CONNECTION SPECIFIED CONDITION REFERENCE TABLE

Tester connection	Spiral cable position	Specified condition
EAU - EAU	Center	Below 1 Ω
	2.5 rotations to the left
	2.5 rotations to the right
AU1 -AU1	Center	Below 1 Ω
	2.5 rotations to the left
	2.5 rotations to the right
AU2-AU2	Center	Below 1 Ω
	2.5 rotations to the left
	2.5 rotations to the right

Fig 3: Identifying Steering Pad Switch Assembly & Spiral Cable Connector Terminals

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 page shown in the brackets.

HINT:

See REMOVAL
See INSTALLATION

NG: REPLACE SPIRAL CABLE

OK: REPAIR OR REPLACE HARNESS OR CONNECTOR (SPIRAL CABLE - RADIO RECEIVER)