Battery Current Sensor

Reconnect harness connectors disconnected.
Disconnect battery negative cable.
Install jumper cable between battery negative terminal and body ground.
Turn ignition switch ON.

Fig 1: Installing Jumper Cable Between Battery Negative Terminal And Body Ground
Courtesy of NISSAN MOTOR CO., U.S.A.
Check voltage between ECM terminal 71 (battery current sensor signal) and ground.
Voltage: Approximately 2.5V

Fig 2: Checking Voltage Between ECM Terminal 71 And Ground
Courtesy of NISSAN MOTOR CO., U.S.A.
If NG, replace battery negative cable assembly.