DTC Troubleshooting: B1827

DTC B1827: Rear Height Pulse Error(no change in pulse for 1 second)

DTC Description	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.
	If DTC B1827 and B1828 are both indicated, check for a blown No. B15 (20 A) fuse in the under-dash fuse/relay box. If the fuse blows again, check for a short to ground in the rear up-down motor circuit.

Problem verification:

Problem verification

?1.	Clear the DTCs with the HDS.

?2.	Press the engine start/stop button at least 20 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?


	DTC B1827 is indicated

Go to step 2.


	DTC B1836 is also indicated

Go to the DTC B1836 troubleshooting.?


	DTC B1825, B1826, and/or B1828 are also indicated

Go to step 6.


	NO

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

Determine possible failure area (motor operation, motor sensor):

Determine possible failure area (motor operation, motor sensor)

?1.	Press the engine start/stop button to select the OFF 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 3.


	NO

Go to step 8.

Open wire check (RHSE, SEG lines):

Open wire check (RHSE, SEG lines)

?1.	Press the engine start/stop button to select the OFF mode.

?2.

Disconnect the following connectors.

Rear up-down motor/position sensor 6P connector

Power seat control unit connector B (20P)

?3.

Check for continuity between test points 1 and 2 respectively.

Test condition	OFF mode Rear up-down motor/position sensor 6P connector: disconnected Power seat control unit connector B (20P): disconnected
Test circuit	RHSE
Test point 1	Rear up-down motor/position sensor 6P connector No. 2 (YEL)
Test point 2	Power seat control unit connector B (20P) No. 9 (YEL)

Test circuit	SEG
Test point 1	Rear up-down motor/position sensor 6P connector No. 6 (WHT)
Test point 2	Power seat control unit connector B (20P) No. 19 (WHT)

Is there continuity?


	YES

The RHSE, SEG wires are not open. Go to step 4.


	NO

Repair an open or high resistance in the wire.?

Shorted wire check (RHSE line):

Shorted wire check (RHSE line)

?1.

Check for continuity between test points 1 and 2.

Test condition	OFF mode Rear up-down motor/position sensor 6P connector: disconnected Power seat control unit connector B (20P): disconnected
Test circuit	RHSE
Test point 1	Power seat control unit connector B (20P) No. 9 (YEL)
Test point 2	Body ground

Is there continuity?


	YES

Repair a short to ground in the wire.?


	NO

The RHSE wire is not shorted. Go to step 5.

Rear up-down position sensor check:

Rear up-down position sensor check

?1.	Reconnect power seat control unit connector B (20P).

?2.	Press the engine start/stop button to select the ON mode.

?3.

Measure the voltage between test points 1(+) and 2(-).

Test condition	ON mode Rear up-down motor/position sensor 6P connector: disconnected
Test circuit	RHSE, SEG
Test point 1	Rear up-down motor/position sensor 6P connector No. 2 (YEL) (+)
Test point 2	Rear up-down motor/position sensor 6P connector No. 6 (WHT) (-)

Is there about 5 V?


	About 5 V

Faulty rear up-down motor/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).?

Open wire check (SVCC, SEG lines):

Open wire check (SVCC, SEG lines)

?1.	Press the engine start/stop button to select the OFF mode.

?2.

Disconnect the following connectors.

Rear up-down motor/position sensor 6P connector

Power seat control unit connector B (20P)

?3.

Check for continuity between test points 1 and 2 respectively.

Test condition	OFF mode Rear up-down motor/position sensor 6P connector: disconnected Power seat control unit connector B (20P): disconnected
Test circuit	SVCC
Test point 1	Rear up-down motor/position sensor 6P connector No. 5 (PUR)
Test point 2	Power seat control unit connector B (20P) No. 6 (PUR)

Test circuit	SEG
Test point 1	Rear up-down motor/position sensor 6P connector No. 6 (WHT)
Test point 2	Power seat control unit connector B (20P) No. 19 (WHT)

Is there continuity?


	YES

The SVCC and SEG wires are OK. Go to step 7.


	NO

Repair an open or high resistance in the wire.?

Power seat control unit check:

Power seat control unit check

?1.	Reconnect power seat control unit connector B (20P).

?2.	Press the engine start/stop button to select the ON mode.

?3.

Measure the voltage between test points 1 and 2.

Test condition	ON mode Rear up-down motor/position sensor 6P connector: disconnected
Test circuit	SVCC, SEG
Test point 1	Power seat control unit connector B (20P) No. 6 (PUR)
Test point 2	Power seat control unit connector B (20P) No. 19 (WHT)

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


	YES

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


	NO

Replace the power seat control unit.?

Fuse check:

Fuse check

?1.

Check the following fuse.

Fuse	No. B15 (20 A)
Location	Under-dash fuse/relay box

Is the fuse OK?


	YES

Go to step 9.


	NO

Replace the fuse. If the fuse blows again, repair the short to ground in the No. B15 (20 A) fuse circuit.?

Open wire check (+B DR P/SEAT REC/VMP2 line):

Open wire check (+B DR P/SEAT REC/VMP2 line)

?1.

Measure the voltage between test points 1 and 2.

Test condition	OFF mode
Test circuit	VMP2

2-door

Test point 1	Power seat control unit connector A (12P) No. 12 (LT BLU)
Test point 2	Body ground

4-door

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

Is there battery voltage?


	YES

The +B DR P/SEAT REC/VMP2 wire is not open. Go to step 10.


	NO

Repair an open or high resistance in the wire.?

10.

Open wire check (PG 2 line):

Open wire check (PG 2 line)

?1.

Measure the voltage between test points 1 and 2.

Test condition	OFF mode
Test circuit	PG 2

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

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

Is there 0.2 V or more?


	YES

Repair an open or high resistance in the ground wire or poor ground (G651).?


	NO

The PG 2 wire is not open. Go to step 11.

11.

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

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

?1.

Disconnect the following connectors.

Rear up-down motor/position sensor 6P connector

Power seat control unit connector A (12P)

?2.

Check for continuity between test points 1 and 2 respectively.

Test condition	OFF mode Rear up-down motor/position sensor 6P connector: disconnected Power seat control unit connector A (12P): disconnected
Test circuit	RR HEIGHT UP
Test point 1	Rear up-down motor/position sensor 6P connector No. 4 (GRN)
Test point 2	Power seat control unit connector A (12P) No. 9 (GRN)

2-door

Test circuit	RR HEIGHT DOWN
Test point 1	Rear up-down motor/position sensor 6P connector No. 3 (WHT)
Test point 2	Power seat control unit connector A (12P) No. 4 (WHT)

4-door

Test circuit	RR HEIGHT DOWN
Test point 1	Rear up-down motor/position sensor 6P connector No. 3 (BRN)
Test point 2	Power seat control unit connector A (12P) No. 4 (BRN)

Is there continuity?


	YES

The RR HEIGHT UP and RR HEIGHT DOWN wires are not open. Go to step 12.


	NO

Repair an open or high resistance in the wire.?

12.

Shorted wire check (RR HEIGHT UP, RR HEIGHT DOWN lines):

Shorted wire check (RR HEIGHT UP, RR HEIGHT DOWN lines)

?1.

Check for continuity between test points 1 and 2 individually.

Test condition	OFF mode Rear up-down motor/position sensor 6P connector: disconnected Power seat control unit connector A (12P): disconnected
Test circuit	RR HEIGHT UP
Test point 1	Rear up-down motor/position sensor 6P connector No. 4 (GRN)
Test point 2	Body ground

2-door

Test circuit	RR HEIGHT DOWN
Test point 1	Rear up-down motor/position sensor 6P connector No. 3 (WHT)
Test point 2	Body ground

4-door

Test circuit	RR HEIGHT DOWN
Test point 1	Rear up-down motor/position sensor 6P connector No. 3 (BRN)
Test point 2	Body ground

Is there continuity?


	YES

Repair a short to ground in the wire.?


	NO

The RR HEIGHT UP and RR HEIGHT DOWN wires are OK. Go to step 13.

13.

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.?