DTC B1826

DTC B1826  : Front height pulse error (no change in pulse for 1 second)

DTC (Power Seat Control Unit)

NOTE: 

• If you are troubleshooting multiple DTCs, be sure to follow the instructions in B-CAN System Diagnosis Test Mode A .
• Before troubleshooting, make sure the fuses associated with the system is OK.

1. Problem verification

   -1. Clear the DTCs with the HDS.

   Clear DTCs

   -2. Press the engine start/stop switch at least twenty times, then wait for at least 20 seconds.

   -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 down position, even when the system is OK.

   -4. Check for DTCs with the HDS.

   DTC Description	DTC
   B1826 Front height pulse error (no change in pulse for 1 second)

   Is DTC B1826 indicated?

   YES 

   Go to step 2.

   NO 

   Intermittent failure, the system is OK at this time. Check for loose or poor connections.

2. DTC check

   -1. Check for DTCs with the HDS.

   DTC Description	DTC
   B1825 Slide pulse error (no change in pulse for 1 second)
   B1826 Front height pulse error (no change in pulse for 1 second)
   B1827 Rear height pulse error (no change in pulse for 1 second)
   B1828 Recline pulse error (no change in pulse for 1 second)
   B1836 Power Seat Position Sensor circuit short

   Any of DTC are indicated at the same time with DTC B1826?

   DTC B1826 is indicated only

   Go to step 3.

   DTC B1836 is also indicated

   Go to the DTC B1836 troubleshooting .

   DTC B1825, B1827, and/or B1828 are also indicated

   Go to step  7.

3. Determine possible failure area (motor operation, motor sensor)

   -1. Turn the vehicle to the OFF (LOCK) mode and then the ON mode.

   -2. 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 4.

   NO 

   Go to step  10.

4. Open wire check (FHSE, SEG lines)

   -1. Turn the vehicle to the OFF (LOCK) mode.

   -2. Disconnect the following connectors.

   Front up-down motor/position sensor 6P connector

   Power seat control unit connector A (20P)

   -3. Check for continuity between test points 1 and 2.

   Test condition	Vehicle OFF (LOCK) mode Front up-down motor/position sensor 6P connector: disconnected Power seat control unit connector A (20P): disconnected
   Test point 1	Front up-down motor/position sensor 6P connector (female terminals) No. 2:
   Test point 2	Power seat control unit connector A (20P) No. 7

   Test point 1	Front up-down motor/position sensor 6P connector (female terminals) No. 6:
   Test point 2	Power seat control unit connector A (20P) No. 19

   Courtesy of HONDA, U.S.A., INC.

   Is there continuity?

   YES 

   The FHSE, SEG wires are not open. Go to step 5.

   NO 

   Repair an open or high resistance in the wire.

5. Shorted wire check (FHSE line)

   -1. Check for continuity between test points 1 and 2.

   Test condition	Vehicle OFF (LOCK) mode Front up-down motor/position sensor 6P connector: disconnected Power seat control unit connector A (20P): disconnected
   Test point 1	Power seat control unit connector A (20P) No. 7

   Test point 2

   Body ground

   Is there continuity?

   YES 

   Repair a short to ground in the wire.

   NO 

   The FHSE wire is not shorted. Go to step 6.

6. Determine possible failure area (Power seat control unit, front up-down position sensor, FHSE line)

   -1. Reconnect the following connector.

   Power seat control unit connector A (20P)

   -2. Turn the vehicle to the ON mode.

   -3. Measure the voltage between test points 1 and 2.

   Test condition	Vehicle ON mode Front up-down motor/position sensor 6P connector: disconnected
   Test point 1	Power seat control unit connector A (20P) No. 7
   Test point 2	Power seat control unit connector A (20P) No. 19

   Is there voltage?

   About 5 V

   Faulty front up-down position sensor; replace the seat frame assembly .

   No voltage

   Replace the power seat control unit .

   Battery voltage

   Repair a short to power in the wire.

7. Open wire check (SEG line)

   -1. Turn the vehicle to the OFF (LOCK) mode.

   -2. Disconnect the following connectors.

   Slide motor/position sensor 6P connector Front up-down motor/position sensor 6P connector Rear up-down motor/position sensor 6P connector Recline motor/position sensor 5P connector Power seat control unit connector A (20P)

   -3. Check for continuity between test points 1 and 2.

   Test condition	Vehicle OFF (LOCK) mode Slide motor/position sensor 6P connector: disconnected Front up-down motor/position sensor 6P connector: disconnected Rear up-down motor/position sensor 6P connector: disconnected Recline motor/position sensor 5P connector: disconnected Power seat control unit connector A (20P): disconnected
   Test point 1	Slide motor/position sensor 6P connector (female terminals) No. 6:
   Test point 2	Power seat control unit connector A (20P) No. 19

   Test point 1	Front up-down motor/position sensor 6P connector (female terminals) No. 6:
   Test point 2	Power seat control unit connector A (20P) No. 19

   Test point 1	Rear up-down motor/position sensor 6P connector (female terminals) No. 6:
   Test point 2	Power seat control unit connector A (20P) No. 19

   Test point 1	Recline motor/position sensor 5P connector (female terminals) No. 4:
   Test point 2	Power seat control unit connector A (20P) No. 19

   Courtesy of HONDA, U.S.A., INC.

   Courtesy of HONDA, U.S.A., INC.

   Is there continuity?

   YES 

   The SEG wire is OK. Go to step 8.

   NO 

   Repair an open or high resistance in the wire.

8. Shorted wire check (SVCC line)

   -1. Check for continuity between test points 1 and 2.

   Test condition	Vehicle OFF (LOCK) mode Slide motor/position sensor 6P connector: disconnected Front up-down motor/position sensor 6P connector: disconnected Rear up-down motor/position sensor 6P connector: disconnected Recline motor/position sensor 5P connector: disconnected Power seat control unit connector A (20P): disconnected
   Test point 1	Power seat control unit connector A (20P) No. 6
   Test point 2	Body ground

   Is there continuity?

   YES 

   Repair a short to ground in the wire.

   NO 

   The SVCC wire is not shorted. Go to step 9.

9. Determine possible failure area (Power seat control unit, SVCC line)

   -1. Reconnect the following connector.

   Power seat control unit connector A (20P)

   -2. Turn the vehicle to the ON mode.

   -3. Measure the voltage between test points 1 and 2.

   Test condition	Vehicle ON mode Slide motor/position sensor 6P connector: disconnected Front up-down motor/position sensor 6P connector: disconnected Rear up-down motor/position sensor 6P connector: disconnected Recline motor/position sensor 5P connector: disconnected
   Test point 1	Power seat control unit connector A (20P) No. 6

   Test point 2

   Power seat control unit connector A (20P) No. 19

   Is there battery voltage when the front up-down switch is operated?

   YES 

   Repair an open or high resistance in the wire.

   NO 

   Replace the power seat control unit .

10. Open wire check (+B DR P/SEAT(SLI) line)

    -1. Measure the voltage between test points 1 and 2.

    Test condition	Vehicle OFF (LOCK) mode
    Test point 1	Power seat control unit connector B (12P) No. 6
    Test point 2	Body ground

    Is there battery voltage?

    YES 

    The +B DR P/SEAT(SLI) wire is not open. Go to step 11.

    NO 

    Repair an open or high resistance in the wire.

11. Open wire check (GND lines)

    -1. Measure the voltage between test points 1 and 2.

    Test condition	Vehicle OFF (LOCK) mode
    Test point 1	Power seat control unit connector B (12P) No. 2
    Test point 2	Body ground

    Test point 1	Power seat control unit connector B (12P) No. 5
    Test point 2	Body ground

    Test point 1	Power seat control unit connector A (20P) No. 20
    Test point 2	Body ground

    Is there 0.2 V or more?

    YES 

    Repair an open or high resistance in the wire or poor ground (G601).

    NO 

    The GND wires are not open. Go to step 12.

12. Open wire check (FR HT UP, FR HT DN lines)

    -1. Disconnect the following connectors.

    Front up-down motor/position sensor 6P connector

    Power seat control unit connector B (12P)

    -2. Check for continuity between test points 1 and 2.

    Test condition	Vehicle OFF (LOCK) mode Front up-down motor/position sensor 6P connector: disconnected Power seat control unit connector B (12P): disconnected
    Test point 1	Front up-down motor/position sensor 6P connector (female terminals) No. 3:
    Test point 2	Power seat control unit connector B (12P) No. 10

    Test point 1	Front up-down motor/position sensor 6P connector (female terminals) No. 4:
    Test point 2	Power seat control unit connector B (12P) No. 7

    Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    The FR HT UP and FR HT DN wires are not open. Go to step 13.

    NO 

    Repair an open or high resistance in the wire.

13. Shorted wire check (FR HT UP, FR HT DN lines)

    -1. Check for continuity between test points 1 and 2.

    Test condition	Vehicle OFF (LOCK) mode Front up-down motor/position sensor 6P connector: disconnected Power seat control unit connector B (12P): disconnected
    Test point 1	Power seat control unit connector B (12P) No. 10
    Test point 2	Body ground

    Test point 1	Power seat control unit connector B (12P) No. 7
    Test point 2	Body ground

    Is there continuity?

    YES 

    Repair a short to ground in the wire.

    NO 

    The FR HT UP and FR HT DN wires are OK. Go to step 14.

14. Front up-down motor check

    -1. Test the front up-down motor .

    Is the motor OK?

    YES 

    Replace the power seat control unit .

    NO 

    Faulty front up-down motor/position sensor; replace the seat frame assembly .