1. Check Refrigerant Pressure Sensor Overall Function

WARNING: This page is about a different car, the 2004 Infiniti Q45. However, it is still accessible from the selected car via links, so may be relevant.

Start engine and warm it up to normal operating temperature.
Turn A/C switch and blower switch ON.
Check voltage between ECM terminal 88 and ground with CONSULT-II or tester.
1. Voltage: 1.0 - 4.0V

Fig 1: Checking voltage between ECM terminal 88 & ground

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

OK or NG

OK: INSPECTION END

NG: GO TO 2.