Windscreen wipers
Windscreen wipers |
The windscreen wiper assembly is located under the cover beneath the windscreen.
The windscreen wipers are controlled by a switch on the steering column to the right of the steering wheel.
The assembly comprises a motor, two wiper arms and an arm linkage that converts motor rotation into wiper movement.
In the motor there is a built-in thermoswitch that trips if the control switch has been activated and the blade has jammed (frozen).
The wiper switch has three positions:
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Intermittent (J)
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Low speed (I)
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High speed (II)
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There is a function in the intermittent position that enables the frequency of wipes to be regulated by a potentiometer. The wipers come on at an interval of between 2 and 15 seconds depending on the setting made. The potentiometer for the intermittent wiper controls the DICE control module which operates the wiper relay.
Intermittent (J)
There is a built-in mechanically controlled connector (31B) in the wiper motor that receives power irrespective of the switch's (61) position. As a result, the intermittent function only requires a start pulse from DICE to become active.When the switch is placed in position (J), power is supplied from pin 10 in switch (61) to pin 21 in DICE (628). The control module emits a start pulse from pin 58 which activates the relay (83). Input voltage is supplied to pin 9 in the switch (61), with output voltage at pin 8. The power supplied to pin 3 in the motor (62F) is equivalent to the low-speed position.
The potentiometer (618) in switch (61) is connected to DICE (628) at pins 55 and 33. Resistance varies between 0 and 1 kohm. The lower value is equivalent to the short interval (2 seconds) and the higher value to the long interval (15 seconds).
The switch (31B) controls the voltage so that the wiper motor always returns to the parking position after the current from the switch has been cut off. When the wiper motor reaches the parking position, the mechanically operated switch cuts off the current and the motor stops until DICE sends the next start pulse.
Low speed (I)
The windscreen wipers operate with approximately 48 double strokes per minute.When switch (61) is placed in position (I), +54 voltage is supplied to the switch via fuse 31. Pin 8 in the switch supplies power to pin 3 in the motor (62F).
High speed (II)
The windscreen wipers operate with approximately 73 double strokes per minute.When switch (61) is placed in position (II), +54 voltage is supplied to the switch via fuse 31. Pin 7 in the switch supplies power to pin 4 in the motor (62F).