Power Supply and Ground Circuit Check for Display Unit and NAVI Switch

WARNING: This page is about a different car, the 2003 Infiniti G35. However, it is still accessible from the selected car via links, so may be relevant.

CHECK FUSE
Check that the following fuses of the display unit and NAVI switch are not blown.

Fig 1: Checking Fuses Of Display Unit And NAVI Switch
Courtesy of NISSAN MOTOR CO., U.S.A.

OK or NG

OK : GO TO 2.

NG : If fuse is blown, be sure to eliminate case of malfunction before installing new fuse. Refer to SYSTEM WIRING DIAGRAMS article.
POWER SUPPLY CIRCUIT CHECK
1. Disconnect display unit and NAVI switch connector.
2. Check voltage between display unit and ground.
  
  Fig 2: Checking Voltage Between Display Unit And Ground (1 Of 2)
  Courtesy of NISSAN MOTOR CO., U.S.A.
  
  Fig 3: Checking Voltage Between Display Unit And Ground (2 Of 2)
  Courtesy of NISSAN MOTOR CO., U.S.A.
3. Check voltage between NAVI switch and ground.
  
  Fig 4: Checking Voltage Between NAVI Switch And Ground (1 Of 2)
  Courtesy of NISSAN MOTOR CO., U.S.A.
  
  Fig 5: Checking Voltage Between NAVI Switch And Ground (2 Of 2)
  Courtesy of NISSAN MOTOR CO., U.S.A.
OK or NG

OK : GO TO 3.

NG : Check the following.
- Harness for open or short between display unit and fuse
- Harness for open or short between NAVI switch and fuse
GROUND CIRCUIT CHECK
1. Check continuity between display unit and ground.
  
  Fig 6: Checking Continuity Between Display Unit And Ground (1 Of 2)
  Courtesy of NISSAN MOTOR CO., U.S.A.
  
  Fig 7: Checking Continuity Between Display Unit And Ground (2 Of 2)
  Courtesy of NISSAN MOTOR CO., U.S.A.
2. Check continuity between NAVI switch harness connector M37 terminal 7 (B) and ground.
  
  Fig 8: Checking Continuity Between NAVI Switch Harness Connector M37 Terminal 7 (B) And Ground
  Courtesy of NISSAN MOTOR CO., U.S.A.
  1. Continuity should exist.
OK or NG

OK : Inspection end.

NG : Repair or replace harness.