Generator malfunctions (VAZ-2115)

Possible generator malfunctions, their causes and solutions:

Cause of malfunction	Method of elimination
The control lamp does not light when the ignition is turned on. Control devices do not work
Fuse F16 in the mounting block has blown	Replace the fuse
Open circuit in the instrument cluster power supply circuit	Check the "O" wire and its connections from the fuse box to the instrument cluster
Open circuit from ignition switch to fuse box	Check the "K" and "G" wires and their connections from the mounting block to the ignition switch
The ignition switch does not work	Check it out, replace the faulty ignition switch contact part
The control lamp does not light when the ignition is turned on and does not light when the engine is running. Control devices work. The battery is discharged
The control lamp has burned out	Replace the indicator lamp
Open circuit in the power supply circuit of the control lamp	Check the "KB" wires and their connections from the generator to the instrument cluster and the reliability of the contact between the terminals of the lamp socket and the instrument cluster board
Wear or sticking of brushes, oxidation of contact rings	Replace the brush holder with brushes, wipe the rings with a napkin soaked in gasoline
The voltage regulator is damaged (open circuit between the "DF" terminal and "ground")	Replace the voltage regulator
The wire from the "D+" terminal of the brush holder has become disconnected	Connect the wire
Short circuit in positive valves	Replace the rectifier unit
Unsoldering the excitation winding leads from the slip rings	Solder the leads or replace the generator rotor
The indicator light is bright or dim when the engine is running. The battery is discharged
Alternator drive belt slippage	Adjust the belt tension
The voltage regulator is damaged	Replace the voltage regulator
The rectifier block valves are damaged	Replace the rectifier unit
The excitation winding power supply diodes are damaged	Replace diodes or rectifier block
Unsoldering the excitation winding leads from the slip rings	Solder the leads or replace the generator rotor
Open or short circuit in the stator winding, shorting it to "ground"	Replace generator stator
The control lamp lights up when the engine is running. The battery is being recharged
The voltage regulator is damaged (short circuit between the "DF" terminal and "ground")	Replace the voltage regulator
Increased generator noise
The generator bearings are damaged	Replace the rear bearing or front cover with bearing
Interturn short circuit or short circuit to ground of the stator winding (generator howl)	Replace the stator
Short circuit in one of the generator valves	Replace the rectifier unit