Inspection Procedure 2: Steering wheel remote control switch illumination does not come on.


TECHNICAL DESCRIPTION (COMMENT)


The power supply circuit to the steering wheel remote control switch, the steering wheel remote control switch, the ETACS-ECU, or the clock spring may be defective.

PROBABLE CAUSES



DIAGNOSIS PROCEDURE


STEP 1. Check the steering wheel remote control switch.


Check the steering wheel remote control switch (Refer to ).

Q. Is the check result normal?

Go to Step 2.

Replace the steering wheel remote control switch.

STEP 2. Resistance measurement at steering wheel remote control switch (LH) connector (earth terminal).


(1)Disconnect the connector, and measure at the wiring harness side.
(2)Measure the resistance between the steering wheel remote control switch (LH) connector (earth terminal) and body earth.
OK: Continuity exists (2 Ω or less)

Q. Is the check result normal?

Go to Step 4.

Go to Step 3.

STEP 3. Check of open circuit in earth line between steering wheel remote control switch (LH) connector and the body earth.


Q. Is the check result normal?

Intermittent malfunction is suspected (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction ).

Repair the connector(s) or wiring harness.

STEP 4. Check the clock spring.


Check whether the clock spring is in good condition. Refer to GROUP 52B - Air bag module and clock spring .

Q. Is the check result normal?

Go to Step 5.

Replace the clock spring.

STEP 5. Check of short to power supply, short to earth, and open circuit in power supply line between ETACS-ECU (tail lamp relay) connector and steering wheel remote control switch (LH) connector.


Q. Is the check result normal?

Go to Step 6.

Repair the connector(s) or wiring harness.

STEP 6. Retest the system.


Check whether the illumination of the steering wheel remote control switch comes on normally.

Q. Is the check result normal?

The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction ).

Replace the ETACS-ECU.