Air Conditioning (A/C) Request Circuit Diagnosis. GMC Truck GMC P42 Commercial Chassis 1998

For 1990-2009 cars only

Makes 🢒 GMC_Truck 🢒 1998 🢒 GMC P42 Commercial Chassis 🢒 Engine 🢒 Engine Controls - 6.5L (L65) 🢒 Air Conditioning (A/C) Request Circuit Diagnosis

Refer to

Engine Controls (Cell 22: A/C Controls)

Engine Controls Components
Engine Controls (Cell 22: A/T Controls 2)
Handling ESD Sensitive Parts Notice
.

Circuit Description

Turning ON the air conditioning supplies ignition voltage to the A/C compressor clutch and to the PCM to increase and maintain idle speed.

The PCM does not control the A/C compressor clutch. Therefore, if the A/C system does not function, refer to Refrigerant System Checks in HVAC Systems - Manual.