DTC U100A[00] Lost Communication With Diff Lock ECU (Information Module)

1. Information module system check

Refer to "64.Body Control 10I.Troubleshooting(Information Module) diagnostic system check - information module".

2. Programming verification

1) Connect the scan tool.

2) Display the Vehicle Configuration All Data Setting / Change on the scan tool and verify that the equipped ECU information is programmed correctly.

3) If it is not programmed correctly, reprogram the correct value.

Refer to "9.Body, Cab, Accessories 9Z.Body, Cab, Accessories Electrical Control information module setting".

Procedure completion

=>Go to Current DTC check.

3. Current DTC check

1) Turn OFF the ignition switch.

2) Turn ON the ignition switch and wait for 5 seconds or more.

3) Observe the DTC information with a scan tool. Is a DTC set?

Yes

=>Go to Rear differential lock control unit communication verification.

No

Go to Intermittent conditions of information module.

Refer to "223.Body Control 36D.Symptom(Information Module) Intermittent Conditions of Information Module".

4. Rear differential lock control unit communication verification

1) Verify that communication can be established with the rear differential lock control unit using the scan tool. Can communication with the rear differential lock control unit be established?

Yes

=>Go to Rear differential lock control unit DTC check.

No (Models with radar sensors/stereo cameras)

Go to Lost communication with the rear differential lock control unit.

Refer to "53.Driveline Control 3A.Troubleshooting(Differential Lock) lost communication with the rear differential lock control unit (models with radar sensor/ stereo camera)".

No (Models without radar sensors and stereo cameras)

Go to Lost communication with the rear differential lock control unit.

Refer to "53.Driveline Control 3A.Troubleshooting(Differential Lock) lost communication with the rear differential lock control unit (models without radar sensor and stereo camera)".

5. Rear differential lock control unit DTC check

1) Observe the rear differential lock control unit DTC information with a scan tool. Is a rear differential lock control unit DTC set?

Yes

Go to the applicable DTC diagnosis.

No

=>Go to CAN communication circuit inspection.

6. CAN communication circuit inspection

1) Inspect the CAN Low circuit and CAN High circuit between the information module (pins 12 and 24 of C105) and the rear differential lock control unit (pins 1 and 9 of C57) for the following. Is the result normal?

Refer to "LHD Controller Area Network (Central Gateway C/U)" in the ETM (wiring diagram). (Open using the ETM viewer.).

Refer to "LHD Controller Area Network (Except Central Gateway C/U)" in the ETM (wiring diagram). (Open using the ETM viewer.).

Refer to "RHD Controller Area Network (Central Gateway C/U (4JJ3 with DPD))" in the ETM (wiring diagram). (Open using the ETM viewer.).

Refer to "RHD Controller Area Network (Central Gateway C/U (4JJ3 without DPD, RZ4E))" in the ETM (wiring diagram). (Open using the ETM viewer.).

Yes

=>Go to Rear differential lock control unit harness connector inspection.

No

Repair the circuit as necessary.

=>Go to Repair verification.

7. Rear differential lock control unit harness connector inspection

1) Inspect for poor connections at the rear differential lock control unit harness connector (pins 1 and 9 of C57). Is the connection status normal?

Refer to "LHD Controller Area Network (Central Gateway C/U)" in the ETM (wiring diagram). (Open using the ETM viewer.).

Refer to "LHD Controller Area Network (Except Central Gateway C/U)" in the ETM (wiring diagram). (Open using the ETM viewer.).

Refer to "RHD Controller Area Network (Central Gateway C/U (4JJ3 with DPD))" in the ETM (wiring diagram). (Open using the ETM viewer.).

Refer to "RHD Controller Area Network (Central Gateway C/U (4JJ3 without DPD, RZ4E))" in the ETM (wiring diagram). (Open using the ETM viewer.).

Yes

=>Go to Information module harness connector inspection.

No

Repair the connections as necessary.

=>Go to Repair verification.

8. Information module harness connector inspection

1) Inspect for poor connections at the information module harness connector (pins 12 and 24 of C105). Is the connection status normal?

Refer to "LHD Controller Area Network (Central Gateway C/U)" in the ETM (wiring diagram). (Open using the ETM viewer.).

Refer to "LHD Controller Area Network (Except Central Gateway C/U)" in the ETM (wiring diagram). (Open using the ETM viewer.).

Refer to "RHD Controller Area Network (Central Gateway C/U (4JJ3 with DPD))" in the ETM (wiring diagram). (Open using the ETM viewer.).

Refer to "RHD Controller Area Network (Central Gateway C/U (4JJ3 without DPD, RZ4E))" in the ETM (wiring diagram). (Open using the ETM viewer.).

Yes

Replace the rear differential lock control unit.

Note

  • Perform programming after replacing the rear differential lock control unit.

Refer to "3.Driveline, Axle 3Z.Driveline, Axle Electrical Control rear differential lock control unit removal".

Refer to "3.Driveline, Axle 3Z.Driveline, Axle Electrical Control rear differential lock control unit installation".

Refer to "3.Driveline, Axle 3Z.Driveline, Axle Electrical Control rear differential lock control unit setting".

=>Go to Current DTC follow-up check.

No

Repair the connections as necessary.

=>Go to Repair verification.

9. Current DTC follow-up check

1) Turn OFF the ignition switch for 30 seconds or more.

2) Turn ON the ignition switch and wait for 5 seconds or more.

3) Observe the DTC information with a scan tool. Is a DTC set?

Yes

=>Go to Information module replacement.

No

=>Go to Repair verification.

10. Information module replacement

Note

  • After replacing the information module, programming must be performed.

Refer to "9.Body, Cab, Accessories 9Z.Body, Cab, Accessories Electrical Control information module removal".

Refer to "9.Body, Cab, Accessories 9Z.Body, Cab, Accessories Electrical Control information module installation".

Refer to "9.Body, Cab, Accessories 9Z.Body, Cab, Accessories Electrical Control information module setting".

Procedure completion

=>Go to Repair verification.

11. Repair verification

1) Turn OFF the ignition switch for 30 seconds or more.

2) Turn ON the ignition switch and wait for 5 seconds or more.

3) Observe the DTC information with a scan tool.