DTC B1846: Power Seat Front Up-Down Switch Circuit Malfunction
| DTC Description | DTC |
|---|---|
| B1846 Power Seat Front 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 - Refer to: Body Electrical Troubleshooting - B-CAN System Diagnosis Test Mode A - Initial Communication and DTC ChecksBody Electrical Troubleshooting - B-CAN System Diagnosis Test Mode 1 and Test Mode 2 (without the HDS)Body Electrical Troubleshooting - B-CAN System Diagnosis Test Mode B - Control Unit Not CommunicatingBody Electrical Troubleshooting - B-CAN System Diagnosis Test Mode C - No DTCs and Output Won't Shut OFFBody Electrical Troubleshooting - B-CAN System Diagnosis Test Mode D - No DTCs and Output Won't Turn ON .
- 1. Problem verification:
1. Clear the DTCs with the HDS.
2. Operate the front up-down switch in each direction for more than 3 seconds.
3. Check for DTCs with the HDS.
DTC Description DTC B1846 Power Seat Front Up-Down Switch Circuit Malfunction Is DTC B1846 indicated?
YES
Go to step 2.
NO
Intermittent failure, the system is OK at this time. Check for loose or poor connections.
- 2. Shorted wire check (FHUP, FHDN, SCOM lines):
1. Disconnect the following connectors.
Power seat control unit connector B (40P) Power seat adjustment switch 12P connector 2. Check for continuity between test points 1 and 2 individually.
Test condition Vehicle OFF (LOCK) mode Power seat control unit connector B (40P): disconnected
Power seat adjustment switch 12P connector: disconnected
Test point 1 Power seat control unit connector B (40P) No. 16 Test point 2 Body ground Test point 1 Power seat control unit connector B (40P) No. 17 Test point 2 Body ground Test point 1 Power seat control unit connector B (40P) No. 20 Test point 2 Body ground Is there continuity?
YES
Repair a short to ground in the wire.
NO
The FHUP, FHDN, and SCOM wires are not shorted. Go to step 3.
- 3. Shorted wire check (FHUP line to FHDN, SCOM lines):
1. Check for continuity between test points 1 and 2 respectively.
Test condition Vehicle OFF (LOCK) mode Power seat control unit connector B (40P): disconnected
Power seat adjustment switch 12P connector: disconnected
Test point 1 Power seat control unit connector B (40P) No. 16 Test point 2 Power seat control unit connector B (40P) No. 20 Test point 1 Power seat control unit connector B (40P) No. 17 Test point 2 Power seat control unit connector B (40P) No. 20 Test point 1 Power seat control unit connector B (40P) No. 16 Test point 2 Power seat control unit connector B (40P) No. 17 Is there continuity?
YES
Repair a short in the wire.
NO
The FHUP, FHDN, and SCOM wires are OK. Go to step 4.
- 4. Power seat adjustment switch check:
1. Test the driver's power seat adjustment switch - Refer to: Driver's Power Seat Adjustment Switch TestDriver's Power Seat Adjustment Switch Test(DPMS) .
Is the switch OK?
YES
Replace the power seat control unit .
NO
Replace the driver's power seat adjustment switch - Refer to: Driver's Power Seat Adjustment Switch Removal and InstallationDriver's Power Seat Adjustment Switch Removal and Installation(DPMS) .