Diagnosis Item 8: 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
The diagnostic result demonstrates that
"the M.U.T.-III cannot receive the sent data from the steering wheel sensor"
when the M.U.T.-III checks the periodically sent data from each ECU and cannot
receive the steering wheel sensor data only.
TROUBLE JUDGEMENT CONDITIONS
M.U.T.-III judges the trouble when
the periodically sent data from steering wheel sensor cannot be received and
sent.
PROBABLE CAUSES
- Damaged harness wires and connectors
- Power supply circuit malfunction of the steering wheel sensor
- Malfunction of the steering wheel sensor
|
STEP 1. Connector check: D-03 joint connector (CAN1) and D-308 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 D-03 joint connector (CAN1) and D-308
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 D-03 joint connector (CAN1) terminal
No.2 and D-308 steering wheel sensor connector terminal
No.3 OK: Continuity (2 Ω or less)
|
|
(5)Continuity between D-03 joint connector (CAN1) terminal
No.13 and D-308 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 .
|
|
|
Q.
Is the check result normal?
|
|
<All the resistances measure 2
Ω or less> Power supply to the steering wheel sensor may be
suspected. Diagnose the steering wheel sensor. Refer to .
|
|
|
|
NO : <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.
|
|
|