Diagnostic Item 18
DIAGNOSTIC ITEM 18: Diagnose the lines between CAN main bus line and the steering wheel sensorCAUTION: When servicing a CAN bus line, ground yourself by touching a metal object such as an unpainted water pipe. If you fail to do so, a component connected to the CAN bus line may be damaged.
(Part 1):
(Part 2):
TROUBLE JUDGMENT
If the M.U.T.-III cannot received signals from the steering wheel sensor, CAN bus line connector(s) are broken or an open circuit has occurred.
COMMENTS ON TROUBLE SYMPTOM
The wiring harness wire or connectors may have loose, corroded, or damage terminals, or terminals pushed back in the connector, or the steering wheel sensor may be defective.
TROUBLESHOOTING HINTS
- The wiring harness or connectors may have loose, corroded, or damage terminals, or terminals pushed back in the connector
- The steering wheel sensor may be defective
DIAGNOSIS
Required Special Tools:
- MB991223: Harness Set
- MB992006: Extra Fine Probe
STEP 1. Check joint connector (4) C-101 and steering wheel sensor connector C-312 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
NOTE: For the removal of the joint connector.
CAUTION: The strand end of the twist wire should be within 10 cm (4 inches) from the connector.
Check the joint connector at the wiring harness side for loose, corroded or damaged terminals, or terminals pushed back in the connector, and also check the short pin behind the connector for corrosion, deformation and delamination.
Q: Are joint connector (4) C-101 and steering wheel sensor connector C-312 in good condition?
YES : Go to Step 2.
NO : Repair the damaged parts. Replace the joint connector as necessary.
STEP 2. Check the CAN bus lines between joint connector (4) and the steering wheel sensor. Measure the resistance between joint connector (4) C-101 and steering wheel sensor connector C-312.
CAUTION:
- A digital multimeter should be used.
- The test wiring harness should be used.
1. Disconnect joint connector (4) C-101 and steering wheel sensor connector C-312, and measure the resistance between each wiring harness side connector.
2. Turn the ignition switch to the "LOCK" (OFF) position.
CAUTION: Disconnect the negative battery terminal.
3. Disconnect the negative battery terminal.
4. Measure the resistance between joint connector (4) terminal 2 and steering wheel sensor connector terminal 4.
OK: 2 ohms or less
5. Measure the resistance between joint connector (4) terminal 13 and steering wheel sensor connector terminal 3.
OK: 2 ohms or less
CAUTION: Strictly observe the specified wiring harness repair procedure.
Q: Do all the resistances measure 2 ohms or less?
YES : [All the resistances measure 2 ohms or less] Power supply to the steering wheel sensor may be suspected. Diagnose the ASC system. Refer to TCL/ASC diagnosis. Inspection Procedure 3: TCL/ASC-ECU Power Supply Supply System
NO : [If either of the resistances measures more than 2 ohms or all the resistances measure more than 2 ohms] Repair the wiring harness between joint connector (4) and the steering wheel sensor connector.