Check Lumbar Support Circuit

1. CHECK LUMBAR SUPPORT SWITCH 
   1. Turn ignition switch OFF.
   2. Disconnect lumbar support switch connector.
   3. Check voltage between lumbar support switch connector B158 terminal 1 and ground.

      1 (R) - Ground: : Battery voltage 

      Fig 1: Identifying Voltage Between Lumbar Support Switch Connector B158 Terminal 1 And Ground

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

   OK or NG 

   OK: GO TO 2.

   NG: Repair or replace harness between fuse block (J/B) and lumbar support switch.

2. CHECK LUMBAR SUPPORT SWITCH 

   Lumbar support switch operate, check continuity lumbar support switch connector B158 terminal 31, 32 and 1, 16B.

   Fig 2: Identifying Continuity Lumbar Support Switch Connector B158 Terminal 31, 32 And 1, 16B

   Courtesy of NISSAN MOTOR CO., U.S.A.
   LUMBAR SUPPORT SWITCH
   
   

   Connector	Terminal		Lumbar support switch condition	Continuity
   B158	31	1	BACKWARD	Yes
   		16B	Other than above	No
   	32	1	FORWARD	Yes
   		16B	Other than above	No

   OK or NG 

   OK: GO TO 3.

   NG: Replace lumbar support switch.

3. CHECK LUMBAR SUPPORT MOTOR HARNESS 
   1. Disconnect lumbar support motor connector.
   2. Check continuity between lumbar support switch connector B158 terminal 31, 32 and lumbar support motor connector B172 terminal 31, 32.

      31 (W) - 31 (W) : Continuity should exist. 

      32 (L) - 32 (L) : Continuity should exist. 

   3. Check continuity between lumbar support switch connector B158 terminal 31, 32 and ground.

      31 (W) - Ground : Continuity should not exist. 

      32 (L) - Ground : Continuity should not exist. 

      Fig 3: Identifying Continuity Between Lumbar Support Switch Connector B158 Terminal 31, 32 And Ground

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

   OK or NG 

   OK: GO TO 4.

   NG: Repair or replace harness between lumbar support switch and lumbar support motor.

4. CHECK LUMBAR SUPPORT SWITCH GROUND CIRCUIT 

   Check continuity between lumbar support switch connector B158 terminal 16B and ground.

   16B (B) - Ground : Continuity should exist. 

   Fig 4: Identifying Continuity Between Lumbar Support Switch Connector B158 Terminal 16B And Ground

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

OK or NG 

OK: Check the condition of the harness and connector.

NG: Repair or replace harness between lumbar support switch and ground.