Check Power Supply and Ground 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 POWER SUPPLY CIRCUIT

Turn ignition switch OFF.
Disconnect Intelligent Key unit connector.
Check voltage between Intelligent Key unit harness connector and ground.

TERMINALS VOLTAGE REFERENCE

Connector	Terminal (Wire color)		Ignition switch position
M75	(+)	(-)	OFF	ACC	ON
	6 (Y/G)	Ground	0V	0V	Battery voltage
	10 (LG)		0V	Battery voltage	Battery voltage
	11 (Y)		Battery voltage	Battery voltage	Battery voltage

Fig 1: Identifying Voltage Between Intelligent Key Unit Harness Connector And Ground

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

OK or NG

OK: GO TO 2.
NG: Repair or replace Intelligent Key power supply circuit.

CHECK GROUND CIRCUIT
Check continuity between Intelligent Key unit harness connector M75 terminal 12 (B) and ground.

12 (B) - Ground : Continuity should exist.

OK or NG
- OK: Power supply and ground circuits are OK.
- NG: Repair or replace the Intelligent Key unit ground circuit.
  
  Fig 2: Identifying Continuity Between Intelligent Key Unit Harness Connector M75 Terminal 12 (B) And Ground
  Courtesy of NISSAN MOTOR CO., U.S.A.