B1826
DTC B1826: Power Seat Front Up-down Motor Pulse ErrorNOTE:
- Make sure you have the latest software on the HDS before troubleshooting.
- If you are troubleshooting multiple DTCs, be sure to follow the instructions in B-CAN System Diagnostic Test Mode A.
- DTC B1826 can be set and stored when the front up-down switch is operated for more than 1 second after the seat has moved to the fully upper or down positions, even if the system is OK.
1. Turn the ignition switch OFF, and then back ON (II).
2. Clear the DTCs with the HDS.
3. Operate the power seat adjustment switch in all directions.
NOTE: Do not hold the switch for more than 1 second after the seat reaches a position limit or a DTC will be set.
4. Check for DTCs with the HDS.
Is DTC B1826 indicated?
YES - Go to step 5.
NO - Intermittent failure. The front up-down motor/position sensor is OK at this time. Check for loose or poor connections and pin fit at the power seat control unit connector. Check the battery condition, battery cable connections, and ground G601.
5. Check for DTCs with the HDS.
Is DTC B1836 also indicated?
YES - go to DTC B1836 troubleshooting.
NO - Go to step 6.
6. Check for DTCs with the HDS.
Are DTCs B1825, B1827, and/or B1828 also indicated?
YES - Go to step 16.
NO - go to step 7.
7. Operate the front up-down switch and check the front up-down motor operation.
NOTE: Do not hold the switch for more than 1 second after the seat reaches a position limit or a DTC will beset.
Does the front up-down motor run smoothly?
YES - Go to step 8.
NO - Go to step 17.
8. Turn the ignition switch OFF.
9. Disconnect the power seat control unit connector A (40P).
10. Disconnect the front up-down motor/position sensor 5P connector.
11. Check for continuity between the power seat control unit connector A (40P) No. 12 and No. 29 terminals and front up-down motor/position sensor 5P connector No. 4 and No. 5 terminals.
Is there continuity?
YES - Go to step 12.
NO - Repair open in the wire
12. Check for continuity between the power seat control unit connector A (40P) No. 12 terminal and body ground.
Is there continuity?
YES - Repair short in the wire to body ground.
NO - Go to step 13.
13. Reconnect the power seat control unit connector A (40P).
14. Turn the ignition switch ON (II).
15. Measure the voltage between the front up-down motor/position sensor 5P connector No. 3 (+) and No. 4 (-) terminals.
Is there about 10 V?
YES - Replace the front up-down motor/position sensor.
NO - Check for an open in the WHT/BLK wire between front up-down motor/position sensor 5P connector No. 3 terminal and power seat control unit connector A (40P) No. 15 terminal. If the wire is OK, substitute a known-good power seat control unit. If the problem is still present, substitute a known-good front up-down motor/position sensor. If the problem is repaired, replace the power seat control unit or front up-down motor/position sensor.
16. Measure the voltage between the power seat control unit connector A (40P) No. 15 and No. 29 terminals.
Is there about 10 V when the front up-down switch is operated?
YES - Replace the front up-down motor/position sensor.
NO - Check the terminal fit. If they are OK, replace the power seat control unit.
17. Turn the ignition switch OFF.
18. Disconnect the power seat control unit connector B (18P).
19. Disconnect the front up-down motor/position sensor 5P connector.
20. Check for continuity between the power seat control unit connector B (18P) No. 6 and 16 terminals and front up-down motor/position sensor 5P connector No. 1 and No. 2 terminals.
Is there continuity?
YES - Go to step 21.
NO - Repair an open in the wire.
21. Check for continuity between the front up-down motor/position sensor 5P connector No. 1 and No. 2 terminals and body ground.
Is there continuity?
YES - Repair a short in the wire.
NO - Go to step 22.
22. Perform the front up-down motor test.
Is the motor OK?
YES - Replace the power seat control unit
NO - Replace the front-up-down motor/position sensor.