Diagnosis Item 8: Diagnose when the M.U.T.-III cannot receive the data sent by A/T-ECU <A/T> or CVT-ECU <CVT>

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

TROUBLE JUDGMENT CONDITIONS

TROUBLESHOOTING HINTS

Malfunction of the connector [joint connector (CAN3) or CVT-ECU connector <CVT> or A/T-ECU <A/T> improperly connected]
Malfunction of the wiring harness [open circuit between the CVT-ECU <CVT> or A/T-ECU <A/T> and the joint connector (CAN3), power supply circuit to the CVT-ECU <CVT> or A/T-ECU <A/T>]
Malfunction of the CVT-ECU <CVT> or A/T-ECU <A/T>

DIAGNOSIS PROCEDURE

STEP 1. Connector check: C-01 joint connector (CAN3) and C-136 CVT-ECU connector <CVT> or C-138 A/T-ECU connector <A/T>

caution

The strand end of the twist wire should be within 10 cm from the connector. For details refer to

Q. Is the check result normal?

	Go to Step 2.

	Repair the defective connector.

STEP 2. Check the wiring harness between C-136 CVT-ECU connector <CVT> or C-138 A/T-ECU connector <A/T> and C-01 joint connector (CAN3)

caution

Strictly observe the specified wiring harness repair procedure. For details refer to

(1)Disconnect CVT-ECU connector <CVT> or A/T-ECU connector <A/T> and joint connector (CAN3), and check the following wiring harness.

(2)Check that there is continuity between C-136 CVT-ECU connector terminal No.4 and C-01 joint connector (CAN3) terminal No.7 <CVT-CAN_H>
OK: Continuity exists (2 Ω or less)

(3)Check that there is continuity between C-136 CVT-ECU connector terminal No.5 and C-01 joint connector (CAN3) terminal No.20 <CVT-CAN_L>
OK: Continuity exists (2 Ω or less)

(4)Check that there is continuity between C-138 A/T-ECU connector terminal No.10 and C-01 joint connector (CAN3) terminal No.7 <A/T-CAN_H>
OK: Continuity exists (2 Ω or less)

(5)Check that there is continuity between C-138 A/T-ECU connector terminal No.11 and C-01 joint connector (CAN3) terminal No.20 <A/T-CAN_L>
OK: Continuity exists (2 Ω or less)

Q. Is the check result normal?

	Check the power supply circuit of the CVT-ECU <CVT> or A/T-ECU <A/T>.Refer to Group 23A - Troubleshooting <CVT> or Group 23C - Troubleshooting <A/T>.

	Repair the wiring harness.