54C-DIAGNOSTICS ITEM 10

Diagnostic Item 10: Diagnose when the scan tool cannot receive the data sent by steering wheel sensor.

caution

When servicing a CAN bus line, ground 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

The diagnostic result demonstrates that "the scan tool (M.U.T.-III) cannot receive the sent data from the steering wheel sensor" when the scan tool (M.U.T.-III) checks the periodically sent data from each ECU and cannot receive the steering wheel sensor data only.

TROUBLE JUDGMENT CONDITIONS

scan tool (M.U.T.-III) judges the trouble when the periodically sent data from steering wheel sensor cannot be received.

PROBABLE CAUSES

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

DIAGNOSIS

STEP 1. Connector check: joint connector (CAN1) and steering wheel sensor connector

caution

The strand end of the twist wire should be within 10 cm (4 inches) 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.

Is the check result normal?

Go to Step 2

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

STEP 2. Resistance measurement at joint connector (CAN1) and 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 joint connector (CAN1) and the steering wheel sensor connector, and measure at the wiring harness side.

(2) Turn the ignition switch to the "LOCK" (OFF) position.

(3)

caution

When measuring the resistance, disconnect the negative battery terminal. For details refer to

Ensure that the negative battery terminal is disconnected.

(4) Continuity between joint connector (CAN1) terminal No.3 and steering wheel sensor connector terminal No.3

OK: Continuity (2 Ω or less)

(5) Continuity between joint connector (CAN1) terminal No.14 and steering wheel sensor connector terminal No.4

OK: Continuity (2 Ω or less)

caution

Strictly observe the specified wiring harness repair procedure. For details refer to

Is the check result normal?

<All the resistances measure 2 Ω or less> Power supply to the steering wheel sensor may be suspected.

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