The system on page 62 was a trinary switch operated system which means the condenser fan and the fan clutch are only on when the head pressure is high enough to close the switch. Because you have a trinary switch the ac relay setup they show in their diagram is unnecessary.
Dual Fan Wiring Chevy Tri Five Forum
Trinary switch wiring diagram. W kenworth ac wiring diagram ci2t together with watch in. Trinary switch wiring diagram. Dakota digital pac 2750 man 650411d pac 2750. Terminal 1 black wire. Trinary switch wiring diagram. Ford or gm pcm with power lead for engine cooling fan 30 85 86 87 87a blue blue red red red purple white white black ground battery auxiliary blue 12v key on ignition source 12v battery or ignition source pcm cooling fan power lead blue blackgreen dark blue blackgreen.
Shown below are the terminal positions typical wiring colors and usage. If the original trinary switch terminals are different a four wire boot connector part number 35900 can be used. In the vintage air diagram you will see that the blue wire on the trinary switch is used to ground switch the coil of the cooling fan relay. Vintage air 18865 goll st. These are listed below. Four seasons trinary switch part numbers are 35889 and 35901.
Jan 13 i was looking at the wiring diagram for your radiator fans on the be cool website. Using a trinary switch can improve system performance extend the life of the radiator fan and in this case simplify the wiring substantially. 1 pac 2750 module 1 rly 3 relay with wiring harness 1 bim data cable 1 bim xx 2 adapter harnesses 1 instruction manual for some options of the pac 2750 additional components are required. San antonio tx 78266 p. When the pressure of the refrigerant in the system exceeds the set point of the trinary switch it will close its contacts and connect the fan trigger to ground. Trinary switch blue blue blue.
Also below is the internal schematic for each of these switches. You may still need a kenworth diagram but the manual will help you identify what kind of switches you have.
Gallery of Trinary Switch Wiring Diagram
