B1012

DTC Troubleshooting: B1000

DTC B1000:

Communication Bus Line Error

NOTE: If you are troubleshooting multiple DTCs, be sure to follow the instructions in B-CAN System Diagnosis Test Mode A Troubleshooting - B-CAN System Diagnosis Test Mode A.

1. Clear the DTCs with the HDS.

2. Turn the ignition switch to LOCK (0) and then back to ON (II).

3. Wait for at least 6 seconds.

4. Check for DTCs with the HDS.

Is DTC B1000 indicated?

YES -

Go to step 5.

NO -

Intermittent failure, the communication bus line is OK at this time. Check for loose or poor connections, or worn/shorted wires. If the connections are good, check the battery condition Battery Test and the charging system.�

5. Check for DTCs with the HDS.

Are DTCs B1000, B1005, B1007, B1011, B1012, B1013, B1015 and B1032 all indicated?

YES -

Go to step 6.

NO -

Faulty MICU; replace the under-dash fuse/relay box.�

6. Turn the ignition switch to LOCK (0).

7. Disconnect the appropriate connector for each control unit in the table one at a time. Clear the DTC, then recheck for DTCs after each unit is disconnected.

NOTE: Leave the control unit connector disconnected after checking for DTCs, before moving on to the next control unit.









Is DTC B1000 indicated with each individual unit disconnected?

YES -

Go to step 8.

NO -

Replace the control unit that was disconnected when B1000 did not reset.�

8. Disconnect rear fuse/relay box connector C (42P).

9. Check for continuity between each of the control unit connector terminals listed in the table and body ground.





Is there continuity?

YES -

Repair a short to ground in the wire between the rear fuse/relay box and the affected control unit.�

NO -

Go to step 10.

10. Measure the voltage between each of the rear fuse/relay box connector terminals listed in the table and body ground.





Is there less than 0.2 V?

YES -

Go to step 11.

NO -

Repair a short to power in the wire between the rear fuse/relay box and the affected control unit.�

11. Check for continuity between under-dash fuse/relay box connector N (45P) terminal No. 22 and body ground.





Is there continuity?

YES -

Repair a short to ground in the wire.�

NO -

Go to step 12.

12. Turn the ignition switch to ON (II).

13. Measure the voltage between under-dash fuse/relay box connector N (45P) terminal No. 22 and body ground.





Is there battery voltage?

YES -

Repair a short to power in the wire.�

NO -

Faulty MICU, replace the under-dash fuse/relay box.�

DTC Troubleshooting: B1012

DTC B1012:

MICU Lost Communication with Rear MICU (RJU Message)

NOTE: If you are troubleshooting multiple DTCs, be sure to follow the instructions in B-CAN System Diagnosis Test Mode A Troubleshooting - B-CAN System Diagnosis Test Mode A.

1. Clear the DTCs with the HDS.

2. Turn the ignition switch to LOCK (0) and then back to ON (II).

3. Wait for at least 6 seconds.

4. Check for DTCs with the HDS.

Is DTC B1012 indicated?

YES -

Go to step 5.

NO -

Intermittent failure, the system is OK at this time. Check for loose or poor connections between the MICU and the rear MICU.�

5. Check for DTCs with the HDS.

Is DTC B1955 indicated with DTC B1012?

YES -

Do the rear MICU input test Rear MICU Input Test.�

NO -

Do the MICU input test MICU Input Test.�