The operation of the voltage regulator is to continuously automatically change the generator excitation current in such a way that the generator voltage is maintained within the specified limits when the generator speed and load current change.
To check and replace the voltage regulator with a capacitor and a brush holder on a car, you will need: screwdrivers with a flat and Phillips blade, a wrench «at 12» (two), DC voltmeter, megohmmeter.
1. Pull out the rubber boot and connect the wire «+» voltmeter to output «B+» generator, and the wire «-» connect to the generator housing.
2. Start the engine and turn on the headlights.
3. After 15 minutes of engine operation at medium speed, measure the voltage, it should be in the range of 14.4-15.1 V. If undercharging or overcharging is observed (voltage is out of range), replace the voltage regulator.
4. The health of the capacitor can be checked with a megger or tester (on a scale of 1-10 MΩ). Connect the tester probes to the capacitor terminals. Before connecting, the device shows infinity. At the moment of connection, the resistance decreases, and then becomes infinite again. In this case, the capacitor is good. A defective capacitor must be replaced.
5. Disconnect the wire from the terminal «minus» battery.
6. Disconnect a socket with wires from conclusions of the generator.
7. Turn away a nut and disconnect wires from a contact hairpin.
Note. The work of replacing the voltage regulator is performed on the generator installed on the car. For clarity, the generator is removed from the car.
8. Having pressed three latches, remove a plastic casing from the generator.
9. Disconnect the connector with the wire from the output of the diode bridge of the generator...
10.... holding the nut with one wrench, unscrew the sleeve from the output bolt with the other «B+»...
11.... and remove the sleeve, spring and flat washers.
12. Remove the two screws securing the voltage regulator to the generator...
13.... and remove the voltage regulator.
14. Check the ease of movement of the brushes in the brush holder and their protrusion. If the brushes protrude from the brush holder by less than 5 mm, replace the voltage regulator with the brush holder.
15. Install the voltage regulator on the vehicle in the reverse order of removal.