Rear Power Seat Control System

SEAT: REAR POWER SEAT CONTROL SYSTEM: B2654: Headrest Sensor Malfunction

DTC B2654 - Headrest Sensor Malfunction

DESCRIPTION

When the position control ECU does not receive a sensor signal despite upward or downward movement of the headrest by power seat motor operation, this DTC is output.






WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. CHECK FOR DTC
(a) DTC output area check
(1) Using the intelligent tester, determine the area that output the DTC.

Result





B -- PERFORM ACTIVE TEST USING INTELLIGENT TESTER OR TECHSTREAM (POWER SEAT MOTOR FUNCTION)
A -- Continue to next step.
2. PERFORM ACTIVE TEST USING INTELLIGENT TESTER OR TECHSTREAM (POWER SEAT MOTOR FUNCTION)
(a) Select the ACTIVE TEST, use the intelligent tester or Techstream to generate a control command, and then check the power seat motor function.
(1) Intelligent tester

RL-SEAT





(2) Techstream

Rear Left Seat





OK:
Motor operates normally.
NG -- CHECK REAR NO. 1 SEAT HEADREST ADJUSTER SUB-ASSEMBLY (POWER SEAT MOTOR)
OK -- Continue to next step.
3. CHECK HARNESS AND CONNECTOR (POSITION CONTROL ECU LH - REAR HEADREST MOTOR LH)





(a) Disconnect the f25 ECU connector.
(b) Disconnect the f26 motor connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard resistance:






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
4. CHECK REAR NO. 1 SEAT HEADREST ADJUSTER SUB-ASSEMBLY (POSITION CONTROL SENSOR)





(a) Disconnect the f26 motor connector.
(b) Measure the voltage according to the value(s) in the table below.
Standard voltage:






NG -- REPLACE POSITION CONTROL ECU LH
OK -- Continue to next step.
5. CHECK REAR NO. 1 SEAT HEADREST ADJUSTER SUB-ASSEMBLY (POSITION CONTROL SENSOR)





(a) Reconnect the f26 motor connector.
(b) Measure the voltage according to the value(s) in the table below.
Standard voltage:






NG -- REPLACE REAR NO. 1 SEAT HEADREST ADJUSTER SUB-ASSEMBLY
OK -- Continue to next step.
6. CHECK FOR DTC
(a) Recheck for the DTC Rear Power Seat Control System.
OK:
DTC B2654 is not output.
NG -- REPLACE POSITION CONTROL ECU LH
OK -- USE SIMULATION METHOD TO CHECK
7. CHECK REAR NO. 1 SEAT HEADREST ADJUSTER SUB-ASSEMBLY (POWER SEAT MOTOR)





(a) Check operation of the power seat motor (headrest motor).
(b) Check if the seat headrest adjuster moves smoothly when the battery is connected to the headrest motor connector terminals.
OK:






NG -- REPLACE REAR NO. 1 SEAT HEADREST ADJUSTER SUB-ASSEMBLY
OK -- Continue to next step.
8. CHECK HARNESS AND CONNECTOR (POSITION CONTROL ECU LH - REAR HEADREST MOTOR LH)





(a) Disconnect the f24 ECU connector.
(b) Disconnect the f26 motor connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard resistance:






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- REPLACE POSITION CONTROL ECU LH
9. PERFORM ACTIVE TEST USING INTELLIGENT TESTER OR TECHSTREAM (POWER SEAT MOTOR FUNCTION)
(a) Select the ACTIVE TEST, use the intelligent tester or Techstream to generate a control command, and then check the power seat motor function.
(1) Intelligent tester

RR-SEAT





(2) Techstream

Rear Right Seat





OK:
Motor operates normally.
NG -- CHECK REAR NO. 1 SEAT HEADREST ADJUSTER SUB-ASSEMBLY (POWER SEAT MOTOR)
OK -- Continue to next step.
10. CHECK HARNESS AND CONNECTOR (POSITION CONTROL ECU RH - REAR HEADREST MOTOR RH)





(a) Disconnect the f5 ECU connector.
(b) Disconnect the f6 motor connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard resistance:






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
11. CHECK REAR NO. 1 SEAT HEADREST ADJUSTER SUB-ASSEMBLY (POSITION CONTROL SENSOR)





(a) Disconnect the f6 motor connector.
(b) Measure the voltage according to the value(s) in the table below.
Standard voltage:






Result





C -- REPLACE POSITION CONTROL ECU RH
B -- REPLACE POSITION CONTROL ECU RH
A -- Continue to next step.
12. CHECK REAR NO. 1 SEAT HEADREST ADJUSTER SUB-ASSEMBLY (POSITION CONTROL SENSOR)





(a) Reconnect the f6 motor connector.
(b) Measure the voltage according to the value(s) in the table below.
Standard voltage:






NG -- REPLACE REAR NO. 1 SEAT HEADREST ADJUSTER SUB-ASSEMBLY
OK -- Continue to next step.
13. CHECK FOR DTC
(a) Recheck for the DTC Rear Power Seat Control System.
OK:
DTC B2654 is not output.

Result





C -- REPLACE POSITION CONTROL ECU RH
B -- REPLACE POSITION CONTROL ECU RH
A -- USE SIMULATION METHOD TO CHECK
14. CHECK REAR NO. 1 SEAT HEADREST ADJUSTER SUB-ASSEMBLY (POWER SEAT MOTOR)





(a) Check operation of the power seat motor (headrest motor).
(1) Check if the seat headrest adjuster moves smoothly when the battery is connected to the headrest motor connector terminals.
OK:






NG -- REPLACE REAR NO. 1 SEAT HEADREST ADJUSTER SUB-ASSEMBLY
OK -- Continue to next step.
15. CHECK HARNESS AND CONNECTOR (POSITION CONTROL ECU RH - REAR HEADREST MOTOR RH)





(a) Disconnect the f4 ECU connector.
(b) Disconnect the f6 motor connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard resistance:






Result





C -- REPAIR OR REPLACE HARNESS OR CONNECTOR
B -- REPLACE POSITION CONTROL ECU RH
A -- REPLACE POSITION CONTROL ECU RH