1996 Peterbilt 379 AC Wiring Diagram

When it comes to the wiring diagram of a 1996 Peterbilt 379 air conditioning system, there are a few things that you need to know. The wiring diagram is essential for anyone who is trying to troubleshoot or repair the AC system. In this article, we will discuss the different components of the AC system and how they are wired together. We will also provide a complete wiring diagram for the 1996 Peterbilt 379 AC system.

Components of the AC System

The AC system in a 1996 Peterbilt 379 consists of several components, including the compressor, condenser, evaporator, accumulator, expansion valve, blower motor, and control panel. Each of these components is connected by wires and electrical connectors. Understanding how these components are wired together is important for troubleshooting and repairing the AC system.

The Compressor

The compressor is the heart of the AC system. It is responsible for compressing the refrigerant and circulating it through the system. The compressor is controlled by the AC relay, which is activated by the AC switch on the control panel. The compressor is connected to the battery through a fuse and a pressure switch. The pressure switch is used to turn off the compressor if the pressure in the system gets too high or too low.

The Condenser

The condenser is located in front of the radiator and is responsible for removing heat from the refrigerant. The condenser is connected to the compressor by a high-pressure line and to the evaporator by a low-pressure line. The condenser fan is controlled by a relay, which is activated by the AC relay. The fan is connected to the battery through a fuse and a temperature switch. The temperature switch is used to turn on the fan when the temperature of the refrigerant gets too high.

The Evaporator

The evaporator is located in the cab of the truck and is responsible for removing heat from the air. The evaporator is connected to the condenser by a low-pressure line and to the expansion valve by a high-pressure line. The blower motor is connected to the evaporator and is controlled by the AC switch on the control panel. The blower motor is connected to the battery through a fuse and a blower motor resistor. The blower motor resistor is used to control the speed of the blower motor.

The Accumulator

The accumulator is located between the evaporator and the compressor and is responsible for storing excess refrigerant. The accumulator is connected to the evaporator by a low-pressure line and to the compressor by a high-pressure line. The accumulator is also connected to the expansion valve by a small refrigerant line.

The Expansion Valve

The expansion valve is located between the accumulator and the evaporator and is responsible for controlling the flow of refrigerant into the evaporator. The expansion valve is controlled by the AC switch on the control panel. The expansion valve is connected to the accumulator by a small refrigerant line and to the evaporator by a high-pressure line.

The Control Panel

The control panel is located in the cab of the truck and is responsible for controlling the AC system. The control panel contains the AC switch, which is used to turn on and off the AC system, and the temperature control, which is used to adjust the temperature of the air coming out of the vents.

Wiring Diagram

Below is a complete wiring diagram for the 1996 Peterbilt 379 AC system. Use this diagram to troubleshoot and repair your AC system.

Component Wire Color Wire Gauge Function
Compressor Red 10 Power
Compressor Green 18 Ground
Compressor Black 18 Pressure Switch
Condenser Fan Orange 10 Power
Condenser Fan Green/Orange 18 Ground
Condenser Fan Blue 18 Temperature Switch
Blower Motor Purple 12 Power
Blower Motor Black 18 Ground
Blower Motor Resistor Yellow/Black 18 Signal
Expansion Valve Pink 18 Signal
Expansion Valve Orange/Yellow 18 Ground
AC Switch Green/White 18 Signal
Control Panel Red/Black 18 Power
Control Panel Red/White 18 Ignition Switch Signal

FAQ

Q: How do I know if my AC system is working properly?

A: If your AC system is working properly, you should feel cold air coming out of the vents in the cab. If the air is warm, the system may be low on refrigerant or there may be a problem with the compressor or other components.

Q: What should I do if my AC system is not working?

A: If your AC system is not working, you should first check the refrigerant level. If the level is low, you may need to recharge the system. If the level is normal, you should check the compressor and other components for any signs of damage or wear.

Q: How often should I have my AC system serviced?

A: You should have your AC system serviced at least once a year to ensure that it is working properly. During the service, a technician will check the refrigerant level, inspect the components for any signs of wear or damage, and perform any necessary repairs or adjustments.

Q: Can I repair my AC system myself?

A: While it is possible to repair some components of your AC system yourself, it is usually best to leave the repairs to a professional technician. AC systems are complex and require specialized tools and knowledge to repair properly.

Q: How much does it cost to repair an AC system?

A: The cost of repairing an AC system depends on the extent of the damage and the cost of the replacement parts. In general, repairs can range from a few hundred dollars to several thousand dollars.

Q: How long does it take to repair an AC system?

A: The time it takes to repair an AC system depends on the extent of the damage and the availability of replacement parts. In general, repairs can take anywhere from a few hours to several days.