DTC B1827

DTC B1827  : Rear 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 .
• Before troubleshooting, make sure the fuses and relays associated with the system is OK.

DTC (Power Seat Control Unit)

1. Problem verification

   -1. Clear the DTCs with the HDS.

   -2. Press the power 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 B1827 is stored when the rear 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
   B1827 Rear height pulse error (no change in pulse for 1 second)

   Is DTC B1827 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 Driver seat recline motor pulse error
   B1836 Power Seat Position Sensor circuit short

   Any of DTC are indicated at the same time with DTC B1827?

   DTC B1827 is indicated only

   Go to step 3.

   DTC B1836 is also indicated

   Go to the DTC B1836 troubleshooting .

   DTC B1825, B1826, 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 rear up-down switch for 2 seconds, and check the rear up-down motor operation.

   Does the rear up-down motor run smoothly?

   YES 

   Go to step 4.

   NO 

   Go to step 10.

4. Open wire check (HESE, SEG lines)

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

   -2. Disconnect the following connectors.

   Rear up-down motor/position sensor 6P connector

   Power seat control unit connector A (20P)

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

   Test condition	Vehicle OFF (LOCK) mode Rear up-down motor/position sensor 6P connector: disconnected Power seat control unit connector A (20P): disconnected
   Test point 1	Rear up-down motor/position sensor 6P connector (female terminals) No. 1:
   Test point 2	Power seat control unit connector A (20P) No. 9

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

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

   Is there 1.0 Ω or less?

   YES 

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

   NO 

   Repair an open or high resistance in the wire.

5. Shorted wire check (HESE line)

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

   Test condition	Vehicle OFF (LOCK) mode Rear 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. 9
   Test point 2	Body ground

   Is there 1.0 MΩ or more?

   YES 

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

   NO 

   Repair a short to ground in the wire.

6. Determine possible failure area (Power seat control unit, rear up-down position sensor, HESE 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 Rear up-down motor/position sensor 6P connector: disconnected
   Test point 1	Power seat control unit connector A (20P) No. 9
   Test point 2	Power seat control unit connector A (20P) No. 19

   Is there voltage?

   About 5 V

   Faulty rear 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 (sensor line).

7. Open wire check (SEG line)

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

   -2. Disconnect the following connectors.

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

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

   Test condition	Vehicle OFF (LOCK) mode Slide motor/position sensor 5P connector: disconnected Front up-down motor/position sensor 6P connector: disconnected Rear up-down motor/position sensor 6P connector: disconnected Recline motor/position sensor 6P connector: disconnected Power seat control unit connector A (20P): disconnected
   Test point 1	Slide motor/position sensor 5P connector (female terminals) No. 3:
   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. 2:
   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. 2:

   Test point 2

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

   Test point 1	Recline motor/position sensor 6P connector (female terminals) No. 2:
   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 1.0 Ω or less?

   YES 

   The SEG wire is OK. Go to step 8.

   NO 

   Repair an open or high resistance in the wire.

8. Shorted wire check (VCC line)

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

   Test condition	Vehicle OFF (LOCK) mode Slide motor/position sensor 5P connector: disconnected Front up-down motor/position sensor 6P connector: disconnected Rear up-down motor/position sensor 6P connector: disconnected Recline 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. 6
   Test point 2	Body ground

   Is there 1.0 MΩ or more?

   YES 

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

   NO 

   Repair a short to ground in the wire.

9. Determine possible failure area (Power seat control unit, VCC 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 5P connector: disconnected Front up-down motor/position sensor 6P connector: disconnected Rear up-down motor/position sensor 6P connector: disconnected Recline motor/position sensor 6P 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 rear 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/P-SEAT2 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. 12
    Test point 2	Body ground

    Is there battery voltage?

    YES 

    The +B/P-SEAT2 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 resistance 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 1.0 Ω or less?

    YES 

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

    NO 

    Repair an open or high resistance in the wire or poor ground (G501).

12. Open wire check (HEIGHT UP, HEIGHT DOWN lines)

    -1. Disconnect the following connectors.

    Rear up-down motor/position sensor 6P connector

    Power seat control unit connector B (12P)

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

    Test condition	Vehicle OFF (LOCK) mode Rear up-down motor/position sensor 6P connector: disconnected Power seat control unit connector B (12P): disconnected
    Test point 1	Rear up-down motor/position sensor 6P connector (female terminals) No. 4:
    Test point 2	Power seat control unit connector B (12P) No. 9

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

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

    Is there 1.0 Ω or less?

    YES 

    The HEIGHT UP and HEIGHT DOWN wires are not open. Go to step 13.

    NO 

    Repair an open or high resistance in the wire.

13. Shorted wire check (HEIGHT UP, HEIGHT DOWN lines)

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

    Test condition	Vehicle OFF (LOCK) mode Rear 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. 9
    Test point 2	Body ground

    Test point 1	Power seat control unit connector B (12P) No. 4
    Test point 2	Body ground

    Is there 1.0 MΩ or more?

    YES 

    The HEIGHT UP and HEIGHT DOWN wires are OK. Go to step 14.

    NO 

    Repair a short to ground in the wire.

14. Rear up-down motor check

    -1. Test the rear up-down motor .

    Is the motor OK?

    YES 

    Replace the power seat control unit .

    NO 

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