B1826
DTC Troubleshooting: B1826
DTC B1826:
Front Height Pulse Error (No Change in Pulse for 1 Second)
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 DTCs with the HDS.
2. Turn the ignition switch to LOCK (0), and then back to ON (II).
3. Operate the power seat adjustment switch for several seconds in each direction.
NOTE: DTC B1826 is stored when the front up-down switch is operated more than 1 second after the seat moves to the most up or most down position, even when the system is OK.
4. Check for DTCs with the HDS.
Is DTC B1826 indicated?
YES -
Go to step 5.
NO -
Intermittent failure, the system is OK at this time. Check for loose or poor connections.
5. Check for DTCs with the HDS.
Is DTC B1836 also indicated?
YES -
Go to the DTC B1836 troubleshooting B1836.
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 17.
NO -
Go to step 7.
7. Turn the ignition switch to LOCK (0), and then back to ON (II).
8. Operate the front up-down switch for 2 seconds, and check the front up-down motor operation.
Does the front up-down motor run smoothly?
YES -
Go to step 9.
NO -
Go to step 24.
9. Turn the ignition switch to LOCK (0).
10. Disconnect power seat control unit connector A (40P).
11. Disconnect the front up-down motor/position sensor 5P connector.
12. Check for continuity between power seat control unit connector A (40P) terminals No. 12 and No. 29 and front up-down motor/position sensor 5P connector terminals No. 5 and No. 4 respectively.
Is there continuity?
YES -
Go to step 13.
NO -
Repair an open or high resistance in the wire(s).
13. Check for continuity between body ground and power seat control unit connector A (40P) terminal No. 12.
Is there continuity?
YES -
Repair a short to ground in the wire.
NO -
Go to step 14.
14. Reconnect power seat control unit connector A (40P).
15. Turn the ignition switch to ON (II).
16. Measure the voltage between front up-down motor/position sensor 5P connector terminals No. 5 (+) and No. 4 (-).
Is there about 5 V?
YES -
Replace the front up-down motor/position sensor Front Seat Up-Down Motor Replacement.
NO -
If there is no voltage, replace the power seat control unit Testing and Inspection. If there is battery voltage, repair a short to power in the wire (sensor line).
17. Turn the ignition switch to LOCK (0).
18. Disconnect power seat control unit connector A (40P).
19. Disconnect the front up-down motor/position sensor 5P connector.
20. Check for continuity between power seat control unit connector A (40P) terminals No. 15 and No. 29 and front up-down motor/position sensor 5P connector terminals No. 3 and No. 4 respectively.
Is there continuity?
YES -
Go to step 21.
NO -
Repair an open or high resistance in the wire(s).
21. Reconnect power seat control unit connector A (40P).
22. Turn the ignition switch to ON (II).
23. Measure the voltage between power seat control unit connector A (40P) terminals No. 15 and No. 29.
Is there battery voltage when the front up-down switch is operated?
YES -
Replace the front up-down motor/position sensor Front Seat Up-Down Motor Replacement.
NO -
Replace the power seat control unit Testing and Inspection.
24. Turn the ignition switch to LOCK (0).
25. Check the No. 19 (20 A) fuse in the driver's under-dash fuse/relay box.
Is the fuse OK?
YES -
Go to step 26.
NO -
Replace the fuse. If the fuse blows again, repair a short to ground on the No. 19 (20 A) fuse circuit.
26. Turn the ignition switch to ON (II).
27. Measure the voltage between body ground and power seat control unit connector B (18P) terminal No. 8.
Is there less than 0.2 V?
YES -
Go to step 28.
NO -
Repair an open or high resistance in the wire between the driver's under-dash fuse/relay box and the power seat control unit.
28. Measure the voltage between body ground and power seat control unit connector B (18P) terminal No. 18, when the front up-down switch is operated.
Is there less than 0.2 V?
YES -
Go to step 29.
NO -
Repair an open or high resistance in the ground wire or poor ground (G701).
29. Turn the ignition switch to LOCK (0).
30. Disconnect power seat control unit connector B (18P).
31. Disconnect the front up-down motor/position sensor 5P connector.
32. Check for continuity between power seat control unit connector B (18P) terminals No. 6 and No. 16 and front up-down motor/position sensor 5P connector terminals No. 2 and No. 1 respectively.
Is there continuity?
YES -
Go to step 33.
NO -
Repair an open or high resistance in the wire(s).
33. Check for continuity between body ground and front up-down motor/position sensor 5P connector terminals No. 1 and No. 2 individually.
Is there continuity?
YES -
Repair a short to ground in the wire(s).
NO -
Go to step 34.
34. Test the front up-down motor Driver's Power Seat Motor Test (With DPMS).
Is the motor OK?
YES -
Replace the power seat control unit Testing and Inspection.
NO -
Replace the front up-down motor/position sensor Front Seat Up-Down Motor Replacement.