11.6.3 System operating principle
11.6.3.1 System operating principle
The front wiper provides a low level signal to the BCM body control unit through a wiper switch,
and the BCM drives the front wiper motor to rotate after receiving the wiper switch driving signal;
and when the wiper switch is in the low gear, the current flows into the armature coil from the
low-speed electric brush of the motor to produce
Motor rotates at a low speed due to large counter electromotive force. When a wiper switch is at
high gear position, current is flowed from a high-speed electric brush of the moor to an armature
coil to generate small counter electromotive force; thus, the motor rotates at a high speed; when
starting a wiper washer switch, a wiper water jet pump is under a working condition; and a wiper
motor also start the low gear to rotate after continually operating the washer switch for 1s.
Deluxe/ultimate vehicle is further equipped with the rain sensor. When the wiper switch is in the
automatic transmission, a rain signal is provided to the BCM according to the rain sensor, and the
revolution speed of the wiper motor is automatically regulated by the BCM, thereby greatly
improving the driving safety and comfort. After closing the wiper switch, the wiper motor does
not stop immediately and continually rotates for a moment under the inertia effect of the armature;
at the same, the armature generates the counter electromotive force to generate electric brake for
the wiper motor, and the motor stop in the fixed position immediately.
The rear wiper switch starts or the rear washer switch starts for 1s continuously, the rear wiper
relay closes, and the terminal No. 3 outputs the power supply to the rear wiper motor, so as to
realize the operation of the rear wiper.
2251