MICU Lost Communication With Door Multiplex Control Unit

DTC Troubleshooting: U0199

DTC U0199:

MICU Lost Communication With Door Multiplex Control Unit

NOTE: If you are troubleshooting multiple DTCs, be sure to follow 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 U0199 indicated?

YES -

Go to step 5.

NO -

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

5. Check for DTCs with the HDS.

Is DTC U1280 indicated?

YES -

Go to the DTC U1280 troubleshooting U1280.�

NO -

Go to step 6.

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

7. Disconnect the power window master switch 37P connector.

8. Disconnect under-dash fuse/relay box connector T (34P).

9. Check for continuity between power window master switch 37P connector terminals No. 33 and No. 35 and under-dash fuse/relay box connector T (34P) terminals No. 29 and No. 12 respectively.





Is there continuity?

YES -

Go to the power window master switch input test, and do all power and ground input tests Power Window Master Switch (Door Multiplex Control Unit) Input Test. If the tests prove OK, replace the power window master switch Power Window Master Switch Replacement.�

NO -

Repair an open or high resistance in the wire.�