Check UART Communication Line Circuit

1. Turn ignition switch OFF.
2. Disconnect driver seat control unit connector and automatic drive positioner control unit connector.
3. Check continuity between driver seat control unit connector B152 terminal 2, 8 and automatic drive positioner connector M49 terminal 10, 26.

   2 (P) - 26 (W) : Continuity should exist. 

   8 (G/Y) - 10 (B) : Continuity should exist. 

4. Check continuity between driver seat control unit connector B152 terminal 2, 8 and ground.

   2 (P) - Ground : Continuity should not exist. 

   8 (G/Y) - Ground : Continuity should not exist. 

   Fig 1: Identifying Continuity Between Driver Seat Control Unit Connector B152 Terminal 2, 8 And Ground

   Courtesy of NISSAN MOTOR CO., U.S.A.

OK or NG 

OK: GO TO 2.

NG: Repair or replace harness between driver seat control unit and automatic drive positioner control unit.

1. Turn ignition switch ON.
2. Check signal between driver seat control unit connector ground, with oscilloscope.
Fig 2: Identifying Signal Between Driver Seat Control Unit Connector Ground, With Oscilloscope
Courtesy of NISSAN MOTOR CO., U.S.A.

Connector	Terminals (Wire color)		Condition	Signal (Reference value)
	(+)	(-)
B152	2 (P)	Ground	Seat memory switch 1 or 2 operation	Courtesy of NISSAN MOTOR CO., U.S.A.

OK or NG 

OK: GO TO 3.

NG: Check the flowing.

• When voltage signal dose not appear with a constant voltage (approx. 5V), replace driver seat control unit.
• When voltage signal dose not appear with a constant voltage (approx. 0V), replace automatic drive positioner control unit.

Check signal between automatic driver positioner control unit connector ground, with oscilloscope.

Fig 3: Identifying Signal Between Automatic Driver Positioner Control Unit Connector Ground, With Oscilloscope

Courtesy of NISSAN MOTOR CO., U.S.A.NISSAN MOTOR CO., U.S.A.

Connector	Terminals (Wire color)		Condition	Signal (Reference value)
	(+)	(-)
M49	10 (B)	Ground	Seat memory switch 1 or 2 operation	Courtesy of NISSAN MOTOR CO., U.S.A.

OK or NG 

OK: GO TO 4.

NG: Check the flowing.

• When voltage signal dose not appear with a constant voltage (approx. 5V), replace automatic driver seat control unit.
• When voltage signal dose not appear with a constant voltage (approx. 0V), replace driver seat control unit.

Dose the automatic drive positioner operate, when the driver seat control unit exchanged?

Does seat memory function operate? 

Yes: Replace automatic drive positioner control unit.

NG: Replace driver seat control unit.