Checking the motor circuit
Note. Before starting the test, study the relevant electrical diagrams. Checking the presence of voltage at the connector terminals is carried out by testing them with a probe of a grounded probe lamp (for 12 V). Turning on the lamp confirms the presence of voltage at the terminal. If it is not possible to identify the cause of the malfunction during the checks described below, the car should be driven to a workshop for a more complete diagnosis of the system.
1. If the windshield wipers are running too slowly, check the battery level first (see chapter Settings and ongoing maintenance). With a good battery, remove the wiper motor (see below) and try to move the brushes by hand, checking the freedom of their movement. If necessary, make the appropriate repair of the rods and lubricate the axle units. Install the electric motor in place, turn on the ignition and restart the brushes. If the speed of the wipers after the corrections made has not returned to normal, check the quality of the contact connections of the circuit and the reliability of fixing the connectors, paying special attention to the condition of the ground. If the circuit is good, replace the electric motor.
2. If the wipers fail to activate, check the condition of the appropriate fuse. If the fuse is OK, install a jumper wire between the drive motor ground terminal and chassis ground. Repeat check. If the wipers now start to function normally, restore the reliability of the ground contact nodes. If the motor still does not run, set the brush control switch to maximum speed (HI) and check the presence of voltage at the connector of the wiring connected to the electric motor.
Note. To gain access to the connector, you will have to remove the front fairing panel (see chapter Body) and assembly of the electric motor.
If voltage is present, test the motor by connecting directly to the battery using a fused jumper wire. If the motor is now running, check the condition of the wiper linkages. If the motor does not start, replace it. If there is no voltage, check the power supply to the wiper control relay. In the presence of voltage on the relay and its absence on the motor, check the correct functioning of the switch (see Section Check of serviceability of functioning and replacement of understeering switches). If the switch is in order, most likely, the built-in control unit has failed, the diagnosis of which must be carried out in a service station using special equipment.
3. If the wipers do not function properly in the interval mode, check the condition of the circuit in the area between the switch and the built-in control unit. If the wiring is OK, check the resistance of the delay time control knob on the combination switch (see Section Check of serviceability of functioning and replacement of understeering switches). With a working handle, it is necessary to diagnose the built-in control unit in a car service.
4. If the brushes stop in the position they occupy when the switch is turned to the OFF position, check the power supply to the motor limit switch. Voltage should be present on the corresponding motor connector wire with the switch turned OFF and the (ON) ignition, otherwise check for an open in the wiring in the section of the circuit between the electric motor and the fuse.
5. If the brushes stop only after the ignition is turned off, disconnect the wiring from the wiper operation control switch. If the brushes stop now, replace the switch. If the brushes continue to function, therefore, the limit switch of the electric motor is damaged, replace the motor.
6. If the brushes do not go under the plane of the hood when stopped, check the drive rod for foreign objects under it. If nothing prevents the brushes from leaving the park position, check the wiring in the section of the circuit between the switch and the motor. If there are no breaks, replace the motor.
Electric motor replacement
1. Remove levers (leashes) windscreen cleaners.
2. Remove the front fairing cover (see chapter Body).
3. Remove from a fairing driving assembly of screen wipers.
4. Turn out bolts of fastening of the motor to driving assembly.
5. Remove the electric motor.
6. Disconnect the electrical wiring from the motor.
7. Installation is carried out in the reverse order.