Toyota Prius 2010 Repair Manual page 37

(b) PTC Heater Assembly Operating Conditions
(1) The PTC heater assembly is turned on and off by the A/C amplifier in accordance with the engine coolant
temperature, ambient temperature, engine speed, temperature setting, and electrical load (generator power
ratio).
12. BLOWER MOTOR
The blower motor has a built-in blower controller, and is controlled using duty control performed by the A/C
amplifier.
13. BUS CONNECTOR (AIR CONDITIONING HARNESS)
(a) A Bus connector is used in the wire harness connection that connects the servo motor from the A/C
amplifier.
2010 Toyota Prius Repair Manual