DTC B1847: Power Seat Rear Up-Down Switch Circuit Malfunction

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).
Operate the rear up-down switch in each direction for at least 6 seconds.
Check for DTCs with the HDS.
Is DTC B1847 indicated?

YES -Go to step 5.

NO -Intermittent failure, the system is OK at this time. Check for loose or poor connections.
Turn the ignition switch to LOCK (0).
Disconnect power seat control unit connector A (40P).
Disconnect the power seat adjustment switch 12P connector.
Check for continuity between body ground and power seat control unit connector A (40P) terminals No. 1, No. 3, and No. 23 individually.

Fig 1: Checking Continuity Between Body Ground And Connector (40P) Terminals
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?

YES -Repair a short to ground in the wire.

NO -Go to step 9.
Check for continuity between these power seat control unit connector A (40P) terminals:
- No. 1 and No. 3
- No. 1 and No. 23
- No. 3 and No. 23
  
  Fig 2: Checking Continuity Between Connector (40P) Terminals
  Courtesy of AMERICAN HONDA MOTOR CO., INC.
  
  Is there continuity?
  
  YES -Repair a short in the wire.
  
  NO -Go to step 10
Do the power seat adjustment switch test (see POWER SEAT ADJUSTMENT SWITCH TEST/REPLACEMENT ).
Is the switch OK?

YES -Replace the power seat control unit.

NO -Replace the power seat adjustment switch.