Diagnosis Item 9: Diagnose when the M.U.T.-III cannot receive the data sent by steering wheel sensor.



caution When servicing a CAN bus line, earth yourself by touching a metal object such as an unpainted water pipe. If you fail to do, a component connected to the CAN bus line may be broken.












FUNCTION




TROUBLE JUDGEMENT CONDITIONS




PROBABLE CAUSES



  • Damaged harness wires and connectors
  • Power supply circuit malfunction of the steering wheel sensor
  • Malfunction of the steering wheel sensor

DIAGNOSIS PROCEDURE


STEP 1. Connector check: B-24 joint connector (CAN1), B-204 steering wheel sensor connector


caution The strand end of the twist wire should be within 10 cm from the connector. For details refer to .

When checking the joint connector, ensure that its wiring harness side and its short pins are not damaged.

Q. Is the check result normal?

Go to Step 2

Repair the defective connector. Replace the joint connector as necessary.

STEP 2. Resistance measurement at B-24 joint connector (CAN1) and B-204 steering wheel sensor connector.


caution A digital multimeter should be used. For details refer to .
caution The test wiring harness should be used. For details refer to .
(1)Disconnect the intermediate connector and the steering wheel sensor connector connector, and measure at the wiring harness side.
(2)Turn the electric motor switch to the LOCK (OFF) position.
(3)
caution When measuring the resistance, disconnect the negative auxiliary battery terminal. For details refer to .
Ensure that the negative auxiliary battery terminal is disconnected.

(4)Continuity between B-24 joint connector (CAN1) terminal No.5 and B-204 steering wheel sensor connector terminal No.3 <LHD>
OK: Continuity (2 Ω or less)

(5)Continuity between B-24 joint connector (CAN1) terminal No.16 and B-204 steering wheel sensor terminal No.4 <LHD>
OK: Continuity (2 Ω or less)
caution Strictly observe the specified wiring harness repair procedure. For details refer to .

(6)Continuity between B-24 joint connector (CAN1) terminal No.4 and B-204 steering wheel sensor connector terminal No.3 <RHD>
OK: Continuity (2 Ω or less)

(7)Continuity between B-24 joint connector (CAN1) terminal No.15 and B-204 steering wheel sensor terminal No.4 <RHD>
OK: Continuity (2 Ω or less)
caution Strictly observe the specified wiring harness repair procedure. For details refer to .

Q. Is the check result normal?

<All the resistances measure 2 Ω or less> Go to Step 3

<Either or all of the resistances measure more than 2 Ω> Repair the wiring harness between joint connector (CAN1) and the steering wheel sensor.

STEP 3. Resistance measurement at B-204 steering wheel sensor connector.


caution A digital multimeter should be used. For details refer to .
(1)Remove the steering wheel sensor, and measure at the equipment side.

(2)Resistance between B-204 steering wheel sensor connector terminal Nos.3 and 4
OK: 120 ± 20 Ω
caution Strictly observe the specified wiring harness repair procedure. For details refer to .

Q. Is the check result normal?

<1 kΩ or more> Power supply to the steering wheel sensor may be suspected. Diagnose the steering wheel sensor. Refer to .

<Less than 1 kΩ> Replace the steering wheel sensor