Check UART Communication Line Circuit

WARNING: This page is about a different car, the 2006 Infiniti G35. However, it is still accessible from the selected car via links, so may be relevant.

CHECK UART LINE HARNESS
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 B352 terminal 1, 17 and automatic drive positioner connector M96 terminal 10, 26.
  17 (R/Y) - 26 (R/G): Continuity should exist .
  
  1 (L/W) - 10 (R/L): Continuity should exist .
4. Check continuity between driver seat control unit connector B352 terminal 1, 17 and ground.
  17 (R/Y) - Ground: Continuity should not exist .
  
  1 (L/W) - Ground: Continuity should not exist .
  
  Fig 1: Checking Continuity Between Driver Seat Control Unit And Automatic Drive Positioner Connector Terminals
  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.

CHECK UART LINE SIGNAL 1

Turn ignition switch ON.

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

Fig 2: Checking Signal Between Driver Seat Control Unit Connector Ground

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

SIGNAL CHECK TABLE

Connector	Terminals (Wire color)		Condition	Signal (Reference value)
Connector	(+)	(-)	Condition	Signal (Reference value)
B352	17 (R/Y)	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 does not appear with a constant voltage (approx. 5V), replace driver seat control unit.
When voltage signal does not appear with a constant voltage (approx. 0V), replace automatic drive positioner control unit.

CHECK UART LINE SIGNAL 2

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

SIGNAL CHECK TABLE

Connector	Terminals (Wire color)		Condition	Signal (Reference value)
Connector	(+)	(-)	Condition	Signal (Reference value)
M96	10 (R/Y)	Ground	Seat memory switch 1 or 2 operation	Courtesy of NISSAN MOTOR CO., U.S.A.

Fig 3: Checking Signal Between Automatic Driver Positioner Control Unit Connector And Ground

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

OK or NG

OK: GO TO 4.

NG: Check the flowing.

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

CHECK DRIVER SEAT CONTROL UNIT
Dose the automatic drive positioner operate, when the driver control unit exchanged?

Does seat memory function operate?

YES: Replace automatic drive positioner control unit.

NG: Replace driver seat control unit.