DTC Troubleshooting: B1827 - Honda CR-V RW/RT 2017-2020

1.

Problem verification:

Problem verification

?1.	Clear the DTCs with the HDS.

?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 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:

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 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):

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):

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.

Check for continuity 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

Is there continuity?


	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):

Shorted wire check (HESE line)

?1.

Check for continuity 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 continuity?


	YES

Repair a short to ground in the wire.?


	NO

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

6.

Determine possible failure area (Power seat control unit, rear up-down position sensor, HESE line):

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):

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.

Check for continuity 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

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 (VCC line):

Shorted wire check (VCC line)

?1.

Check for continuity 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 continuity?


	YES

Repair a short to ground in the wire.?


	NO

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

9.

Determine possible failure area (Power seat control unit, VCC line):

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):

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):

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 (G501).?


	NO

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

12.

Open wire check (HEIGHT UP, HEIGHT DOWN lines):

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.

Check for continuity 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

Is there continuity?


	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):

Shorted wire check (HEIGHT UP, HEIGHT DOWN lines)

?1.

Check for continuity 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 continuity?


	YES

Repair a short to ground in the wire.?


	NO

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

14.

Rear up-down motor check:

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.?