Diagnosis Item
14: Diagnose the lines between the joint connectors (CAN3 and CAN1).
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 "diagnose the lines between the joint connectors
(CAN3 and CAN1)" when the M.U.T.-III checks the periodically sent data from each ECU and cannot
receive the engine-ECU data.
TROUBLE JUDGEMENT CONDITIONS
M.U.T.-III judges the trouble when the periodically sent data from engine-ECU cannot be
received.
PROBABLE CAUSE
Damaged harness wires and connectors
|
STEP 1. Connector check: C-126 intermediate connector, joint
connector (CAN3) and joint connector (CAN1)
|
|
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 joint connector (CAN3) and C-126
intermediate 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 joint connector (CAN3) and the intermediate 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 (CAN3) terminal No.10 and C-126 intermediate
connector terminal No.15 OK: Continuity (2 Ω or less)
|
|
(5)Continuity between joint connector (CAN3) terminal No.21 and C-126 intermediate
connector terminal No.16 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
.
|
|
|
|
NO : <Either or all of the resistances measure more than 2 Ω> Repair
the wiring harness between joint connector (CAN3) and intermediate connector C-126.
|
|
|
|
STEP 3. Resistance measurement at joint connector (CAN1) and C-126
intermediate 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 intermediate 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.11 and C-126 intermediate
connector terminal No.15 OK: Continuity (2 Ω or less)
|
|
(5)Continuity between joint connector (CAN1) terminal No.22 and C-126 intermediate
connector terminal No.16 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> Follow diagnosis
item 13, 14, 16, 17, 18, 19, 20, 21and 22. Refer to .
|
|
|
|
NO : <Either or all of the resistances measure more than 2 Ω> Repair
the wiring harness between joint connector (CAN1) and intermediate connector C-126.
|
|
|