Sprinter 2500 V6-3.0L DSL Turbo VIN 45 (2007)
Control Module HVAC: Description and Operation
Front Blower Motor Power Module - Operation
OPERATION
The blower motor power module is connected to the vehicle electrical system through a lead and connector of the HVAC wire harness. The blower
motor power module allows the microprocessor-based automatic temperature control (ATC) A/C-heater control to calculate and provide infinitely
variable blower motor speeds based upon either manual blower switch input or the ATC programming using a pulse width modulated (PWM) circuit
strategy.
The PWM voltage is applied to a comparator circuit which compares the PWM signal voltage to the blower motor feedback voltage. The resulting
output drives the power module circuitry, which provides a linear output voltage to change or maintain the desired blower speed.
The blower motor power module is diagnosed using a scan tool.
The blower motor power module cannot be adjusted or repaired and must be replaced if inoperative or damaged.
