Motor, air mixing damper, right (222RH)
Motor, air mixing damper, right (222RH) |
Location |
Motor, air mixing damper, right (222RH) .
Main function |
The stepping motor is connected by a linkage to and controls the air mixing damper for the left climate zone.
Type |
The unipolar stepping motor consists of a rotor (10 poles) and four stator windings. A gearbox transfers the power from the rotor to the lever which controls the damper.
Connection |
The four stepping motor windings receive a common B+ feed from ACC unit pin 20 (K42) and grounds each corresponding winding (pin 11, 31, 10 and 30 in K42) in a specific order thus operating the motor in short pulses, which explains the name stepping motor. The rotational direction can be changed.
When the stepping motor is stationary the two windings are continuously ground to lock the motor. The stepping motor does not need to be reconnected to the control module (position sensor), but by sending out a specific number of ground pulses the ACC unit always knows how far the air distribution flap has moved.