DTC U0199: Power seat Control Unit Lost Communication With Door Multiplex Control Unit

WARNING: This page is about a different car, the 2012 Honda Accord, 2011 Honda Accord, 2010 Honda Accord, 2009 Honda Accord, and 2008 Honda Accord. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: If you are troubleshooting multiple DTCs, be sure to follow the instructions in B-CAN System Diagnosis Test Mode A (see TROUBLESHOOTING - B-CAN SYSTEM DIAGNOSIS TEST MODE A ).

Clear the DTCs with the HDS.
Turn the ignition switch to LOCK (0) and then back to ON (II).
Wait for at least 6 seconds.
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 between the power seat control unit and the door multiplex control unit.
From the BODY ELECTRICAL SYSTEM SELECT menu, select B-CAN CONTROL UNITS INFORMATION, and then select CHECK CONNECTED CONTROL UNITS.
Is the power window unit detected?

YES -Go to step 9.

NO -Go to step 6.
Measure the voltage between body ground and power window master switch 37P connector terminal No. 13.

Fig 1: Measuring Voltage Between Body Ground & Power Window Master Switch 37P Connector Terminal No. 13

Is there battery voltage?

YES -Go to step 8.

NO -Go to step 7.
Check the No. 15 (10 A) fuse in the under-hood fuse/relay box.
Is the fuse OK?

YES -Repair an open or high resistance in the No. 15(10 A) fuse circuit.

NO -Replace the fuse. If the fuse blows again, repair a short to ground on the No. 15 (10 A) fuse circuit.
Measure the voltage between body ground and power window master switch 37P connector terminals No. 32 and No. 37 individually.

Fig 2: Measuring Voltage Between Body Ground And Power Window Master Switch 37P Connector Terminals No. 32 & No. 37 Individually

Is there less than 0.2 V?

YES -Go to step 9.

NO -Repair an open or high resistance in the ground wire(s) or poor ground (G501) and/or (G502).
Turn the ignition switch to LOCK (0).
Disconnect power seat control unit connector B (40P).
Disconnect the power window master switch 37P connector.
Check for continuity between power window master switch 37P connector terminals No. 33 and No. 35 and power seat control unit connector B (40P) terminals No. 39 and No. 40 respectively.

Fig 3: Checking Continuity Between Power Seat Control Unit Connector B (40P) Terminals No. 33 And No. 35
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?

YES -Replace the door multiplex control unit, 4-door (see POWER WINDOW MASTER SWITCH REPLACEMENT ), 2-door (see 2-DOOR ).

NO -Repair an open or poor connection in the B-CAN wire(s) between the power seat control unit and the door multiplex control unit.