Control Module HVAC: Description and Operation

1992 Volvo 740 L4-2320cc 2.3L DOHC B234F (Can)SECTION Description and Operation




Fan Control Module (Power Stage):
^ The Power Stage amplifies the control signals to operate the blower motor and control compressor operation.
^ The blower speed is controlled by a power transistor. A relay is connected into the circuit at the highest speed reduce the load on the transistor, while a second relay controls the operation of the compressor through the low-pressure pressostat on the air receiver/dryer.

RENDER: 1.0x

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