B1826
DTC B1826: Front Up-down Motor Pulse ErrorNOTE: If you are troubleshooting multiple DTCs, be sure to follow the instructions in B-CAN system diagnosis test mode A
1. Clear the DTC with the HDS.
2. Turn the ignition switch OFF, and then back ON (II).
3. Move the front of the power seat up and down with the power seat adjustment switch for more than 2 seconds in each direction
Does the motor run continuously for more than 2 seconds?
YES - Intermittent failure, the system is OK at this time Check for a poor connection at the sensor and at the power seat control unit connector A (20P).
NO - Go to step 4.
4. Move the power seat up and down with the power seat adjustment switch again
Does the motor run for about 1 second?
YES - Go to step 5
NO - Go to step 16
5. Turn the ignition switch OFF
6. Remove the driver's power seat
7. Disconnect the power seat control unit connector A (20P), slide position sensor connector (3P), and front up-down motor/position sensor connector (5P)
8. Check for continuity between the front up-down motor/position sensor connector (5P) No 5 terminal and power seat control unit connector A (20P) No 12 terminal
Is there continuity?
YES - Go to step 9.
NO - Repair open in the GRN/BLK wire.
9. Check for continuity between the front up down motor/position sensor connector (5P) No 5 terminal and body ground
Is there continuity?
YES - Repair a short in the GRN/BLK wire.
NO - Go to step 10
10. Check for continuity between the front up-down motor/position sensor connector (5P) No. 3 terminal and power seat control unit connector A (20P) No. 1 terminal.
Is there continuity?
YES - Go to step 11.
NO - Repair open in the BRN wire.
11. Check for continuity between the front up-down motor/position sensor connector (5P) No. 3 terminal and body ground.
Is there continuity?
YES - Repair a short in the BRN wire.
NO - Go to step 12.
12. Check for continuity between the front up-down motor/position sensor connector (5P) No. 4 terminal and power seat control unit connector A (20P) No. 11 terminal.
Is there continuity?
YES - Go to step 13.
NO - Repair open in the WHT/BLK wire.
13. Reconnect the power seat control unit connector A (20P).
14. Turn the ignition switch ON (II).
15. Measure voltage between the power seat control unit connector A (20P) No. 1 and No. 11 terminals.
Is there about 5 V?
YES - Replace the front up-down motor/position sensor.
NO - Replace the power seat control unit.
16. Turn the ignition switch OFF.
17. Check the No. 14 (20 A) fuse in the under-dash fuse/relay box.
Is the fuse OK?
YES - Go to step 18.
NO - Replace the fuse and retest. If the fuse blows again, repair the short in the wire.
18. Disconnect the power seat control unit connector B (8P).
19. Measure the voltage between the No. 3 terminal of power seat control unit connector B (8P) and body ground.
Is there battery voltage ?
YES - Go to step 20.
NO - Repair an open in the wire between the under-dash fuse/relay box and the power seat control unit.
20. Check for continuity between the No. 7 terminal of power seat control unit connector B (8P) and body ground.
Is there continuity?
YES - Go to step 21.
NO - Repair an open in the wire between the power seat control unit and G503, G601. If the wire is OK, repair G503, G601.
21. Disconnect the front up-down motor connector (5P).
22. Check for continuity between the following terminals of the power seat control unit connector B (8P) and the front up-down motor connector (5P).
Is there continuity?
YES - Go to step 23.
NO - Repair an open in the wire between the power seat control unit connector B (8P) and the front up-down motor connector (5P).
23. Remove the driver's power seat.
24. Test the front up-down motor.
Is the front up-down motor OK?
YES - Repair an open or a short in the front up-down motor/position sensor wires.
NO - Replace the front up-down motor/position sensor.