1. Remember that charging system malfunctions are not necessarily related to generator failures.
Always do the following simple checks first:
- a) Check the condition of the battery wires at the places where they are connected to the terminals of the latter. Check the reliability of the fastening of the terminal clamps;
- b) Check Battery Status (see Section Checking the condition and replacing the battery). If necessary, recharge the latter, or replace it with a new one;
- c) Check the condition of the wiring and electrical connections of the generator and voltage regulator;
- d) Check the condition and tension of the alternator drive belt (see chapter Settings and ongoing maintenance). Replace if necessary;
- e) Check up reliability of a tightening of bolts of fastening of the generator;
- f) Start the engine and evaluate the intensity of the background noise emitted by the generator;
- g) If equipped, check the condition of the fuses in the mounting block in the engine compartment of the car (see chapter Onboard electrical equipment).If any of the inserts fail, investigate and eliminate the cause of the overload;
- h) Check the operation of the charge indicator lamp in the engine instrument panel. With the ignition on and the engine off, the lamp should be on. Otherwise, disconnect the 4-pin connector on the back of the generator and ground terminal #3 (V6 engines) or #4 (4-cylinder engines). If the lamp does not turn on now, check the condition of the No. 6 fuse for 15 A, as well as the filament of the lamp itself. Make the necessary replacements;
- i) Check the contents of the on-board processor memory block for the presence of fault codes of the electrical load monitoring system recorded in it (ELD) (see chapter Engine management).
2. Turning off the ignition, use a voltmeter to measure the voltage generated by the battery at the back of the generator with the consumers of electricity disconnected (heater fan, radio, cigarette lighter, cooling fan, etc. and so on.). The result of the measurement should be about 12.5 V, or slightly higher if the engine has been running for the last hour.
3. Start the engine and repeat the measurement. At a crankshaft speed of 1500 rpm, the voltage should be 13.8 ÷ 14.8 V.
4. Turn on the high beam headlights, start the K / V fan at maximum speed, turn on the rear window heating and the radio. During the normal functioning of the charge system, the voltage should drop for a short time, then return to the normal operating level of about 13.5 V. If the voltage drops below 13 V, then the system is not functioning properly.
5. Reset the engine speed to idle - the charge voltage should not fall below the value of 13 V. depressing the foot brake should not lead to a further decrease in voltage (below 13 V).
Note. Some low-power generators may allow the output voltage to drop below 13 V for a short time, but then it should quickly recover.
6. Turn off all consumers of electricity, raise the engine speed to 1600 per minute and read the voltmeter reading again. Now the voltage should not rise above 15 V (slight deviations are permissible, inversely related to the ambient temperature).
7. If the voltmeter registers values other than the specified values, the generator assembly with the voltage regulator should be replaced.