B1843
DTC Troubleshooting: B1843
DTC B1843:
UART Communication Error
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 DTC with the HDS.
2. Turn the ignition switch to LOCK (0), and then back to ON (II), or press the engine start/stop button to select the OFF mode and then the ON mode.
3. Operate the power seat with the driving position memory switch.
4. Check for DTCs with the HDS.
Is DTC B1843 indicated?
YES -
Go to step 5.
NO -
Intermittent failure, the system is OK at this time.�
5. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.
6. Disconnect the power seat control unit connectors and power mirror control unit connector (24P).
7. Check for continuity between power seat control unit connector B (40P) terminal No. 38 and power mirror control unit connector (24P) terminal No. 13.
Is there continuity?
YES -
Go to step 8.
NO -
Repair an open in the wire between the power mirror control unit connector (24P) and power seat control unit connector B (40P).�
8. Check for continuity between body ground and power seat control unit connector B (40P) terminal No. 38.
Is there continuity?
YES -
Repair a short to ground in the wire.�
NO -
Go to step 9.
9. Reconnect the power mirror control unit connector (24P).
10. Measure the voltage between body ground and power mirror control unit connector (24P) terminal No. 24.
Is there battery voltage?
YES -
Go to step 11.
NO -
Check No. 15 (10 A) fuse in the under-hood fuse/relay box. If the fuse is OK, repair an open in the wire.�
11. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.
12. Measure the voltage between body ground and power mirror control unit connector (24P) terminal No. 22.
Is there less than 0.2 V?
YES -
Replace the power mirror control unit Service and Repair.�
NO -
Repair an open or high resistance in the wire between the power mirror control unit and G401. If the wire is OK, repair G401.�