Diagnosis Item
30: Diagnose when the M.U.T.-III cannot receive the data sent by combination meter.
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 combination meter" when the M.U.T.-III checks the periodically sent data from each ECU and
cannot receive the combination meter data only.
TROUBLE JUDGEMENT CONDITIONS
M.U.T.-III judges the trouble when the periodically sent data from combination meter cannot
be received.
PROBABLE CAUSES
Damaged harness wires and connectors
Power supply circuit malfunction of the combination meter
Malfunction of the combination meter
DIAGNOSIS PROCEDURE
STEP 1. Connector check: joint connector (CAN5) and combination
meter 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 joint connector (CAN5) and combination
meter 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 (CAN5) and the combination meter 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 (CAN5) terminal No.9 and combination meter connector
terminal No.14 OK: Continuity (2 Ω or less)
(5)Continuity between joint connector (CAN5) terminal No.20 and combination meter
connector terminal No.15 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 (CAN5) and the combination meter.
STEP 3. Resistance measurement at combination meter connector.
caution
A digital multimeter should be used. For details refer to .
(1)Remove the combination meter, and measure at the equipment side.
(2)Resistance between combination meter connector terminal Nos.14 and 15 OK: 120 ± 20 Ω
caution
Strictly observe the specified wiring harness repair procedure.
For details refer to .
Q.
Is the check result normal?
<Within 120 ± 20 Ω> Power supply to the combination meter
may be suspected. Diagnose the combination meter. Refer to GROUP 54A Combination Meter - Troubleshooting .
<Not within 120 ± 20 Ω> Replace the combination meter.