B2187

DTC Troubleshooting: B2187

DTC B2187:

UART Communication Error 1 (Driver's MPCS Unit from DR Door ECU)

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. Check for DTCs with the HDS.

Is DTC B2187 indicated?

YES -

Go to step 4.

NO -

Intermittent failure, the system is OK at this time.�

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

5. Disconnect front passenger's MPCS unit connector A (28P).

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

7. Clear the DTCs with the HDS.

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

9. Check for DTCs with the HDS.

Is DTC B2187 indicated?

YES -

Go to step 10.

NO -

Do the front passenger's MPCS unit input test, step No. 6. If OK, replace the front passenger's MPCS unit.�

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

11. Disconnect the moonroof control unit/motor 10P connector.

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

13. Clear the DTCs with the HDS.

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

15. Check for DTCs with the HDS.

Is DTC B2187 indicated?

YES -

Go to step 16.

NO -

Replace the moonroof control unit/motor.�

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

17. Disconnect the power window master switch 14P connector.

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

19. Clear the DTCs with the HDS.

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

21. Check for DTCs with the HDS.

Is DTC 2187 indicated?

YES -

Go to step 22.

NO -

Replace the power window master switch.�

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

23. Disconnect driver's MPCS unit connector A (40P).

24. Check for continuity between driver's MPCS unit connector A (40P) terminal No. 8 and body ground.





Is there continuity?

YES -

Repair a short to ground in the wire.�

NO -

Go to step 25.

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

26. Measure the voltage between driver's MPCS unit connector A (40P) terminal No. 8 and body ground.





Is there voltage?

YES -

Repair a short to power in the wire.�

NO -

Replace the driver's MPCS unit.�