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Diagnostic Item 13: Diagnose the lines between the joint connectors (CAN1 and CAN2)
 
 
cautionWhen 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 "diagnose the lines between the joint connectors (CAN1 and CAN2)" when the scan tool (M.U.T.-III) checks the periodically sent data from each ECU and cannot receive the engine control module (ECM) data.
 
 
TROUBLE JUDGMENT CONDITIONS
scan tool (M.U.T.-III) judges the trouble when the periodically sent data from engine control module (ECM) cannot be received.
 
 
PROBABLE CAUSE
Damaged harness wires and connectors
 
 
DIAGNOSIS
STEP 1. Connector check: C-212 intermediate connector, joint connector (CAN1) and joint connector (CAN2)
cautionThe 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 C-212 intermediate connector.
cautionA digital multimeter should be used. For details refer to .
cautionThe test wiring harness should be used. For details refer to .
(1) Disconnect the 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)
cautionWhen 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.9 and C-212 intermediate connector terminal No.17
OK: Continuity (2 Ω or less)
(5) Continuity between joint connector (CAN1) terminal No.20 and C-212 intermediate connector terminal No.8
OK: Continuity (2 Ω or less)
cautionStrictly observe the specified wiring harness repair procedure. For details refer to .
Is the check result normal?
<All the resistances measure 2 Ω or less> Go to Step 3.
<Either or all of the resistances measure more than 2 Ω> Repair the wiring harness between joint connector (CAN1) and intermediate connector C-212.
 
STEP 3. Resistance measurement at joint connector (CAN2) and C-212 intermediate connector.
cautionA digital multimeter should be used. For details refer to .
cautionThe test wiring harness should be used. For details refer to .
(1) Disconnect joint connector (CAN2) and the intermediate connector, and measure at the wiring harness side.
(2) Turn the ignition switch to the LOCK (OFF) position.
(3)
cautionWhen 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 (CAN2) terminal No.6 and C-212 intermediate connector terminal No.17
OK: Continuity (2 Ω or less)
(5) Continuity between joint connector (CAN2) terminal No.17 and C-212 intermediate connector terminal No.8
OK: Continuity (2 Ω or less)
cautionStrictly observe the specified wiring harness repair procedure. For details refer to .
Is the check result normal?
<All the resistances measure 2 Ω or less> Follow diagnosis item 5, 6, 7, 8, 9, 10, 11, 12, 14, 15, 16 and 17. Refer to .
<Either or all of the resistances measure more than 2 Ω> Repair the wiring harness between the joint connector (CAN2) and the intermediate connector.