Auxiliary Climate Control

Underbody Auxiliary A/C Lines

NOTE: An in-line filter is installed in the auxiliary evaporator inlet line at the floorpan spring lock coupling connection. A restriction in this filter may cause misdiagnosis of a failed TXV. This filter must be inspected before a new TXV is installed.

The underbody auxiliary A/C lines carry refrigerant to the auxiliary A/C evaporator inlet, and away from the auxiliary A/C evaporator outlet. The auxiliary underbody lines have the following characteristics:
- The front auxiliary A/C evaporator inlet line carries high pressure refrigerant liquid from the condenser to evaporator line to the tube-in-tube type auxiliary evaporator line.
- The front auxiliary A/C evaporator outlet line carries refrigerant vapor from the tube-in-tube type auxiliary evaporator line to the front evaporator outlet line.
- The tube-in-tube type auxiliary evaporator line combines a high-pressure tube and a low-pressure tube into a single assembly. The high-pressure tube is located inside of, and is separate from the low-pressure tube.
- Four short jumper lines connect the tube-in-tube auxiliary evaporator line to the auxiliary evaporator inlet and outlet. The jumper lines are connected at the floorpan bracket.

Underbody Heater Lines
The underbody auxiliary heater lines have the following features:
- The underbody auxiliary heater inlet line is a aluminum tube assembly that carries coolant from the engine coolant supply line to the auxiliary heater core inlet.
- The underbody auxiliary heater outlet line carries coolant from the auxiliary heater core to the front heater core outlet line.