Town Car V8-281 4.6L SOHC (1991)
Thermo Blower Lockout (TBL) Switch: Description and Operation
Fig. 5 Thermal blower lockout switch
The TBL, Fig. 2, is a combination vacuum valve and single-pole single-throw switch powered by a thermal element. The TBL is located in the heater
supply hose in the engine compartment with the thermal element of the switch in contact with engine coolant. With engine cold and function lever in
FLOOR position, blower is locked out and outside-recirc door is in recirc position.
When engine coolant warms to approximately 120°F, the electrical switch contacts close, permitting blower to operate and outside-recirc door to
move to outside position.
