Preparing for the test
Check that the battery installed in the vehicle is fully charged.
Check alternator drive belt tension.
Turn the ignition key to position «OFF».
Disconnect the wire from the negative (–) battery terminals.
Connect a digital voltmeter between the terminal «S (L)» generator and «weight».
Connect first (+) voltmeter lead to terminal «S (L)» generator, then (–) wire to a suitable «mass» (to the body) or to negative (–) battery terminal.
Disconnect the standard wire from the output «IN» generator.
Pic. 7.12. Regulated voltage test circuit
Connect ammeter (DC, with a range of 0-100 A) in series between output «IN» generator and disconnected regular wire. Connect (–) ammeter wire to the disconnected standard wire (pic. 7.12).
Connect a control tachometer according to the manufacturer's instructions. Connect the wire to the negative (–) battery terminal.
Verification procedure
Turn the ignition on and check that the voltmeter shows the specified voltage value (battery voltage).
If the voltmeter shows 0 V, then either an open circuit has occurred between the output «S (L)» generator and positive (+) battery terminal, or the fusible link is blown.
Turn off all lights and additional electrical equipment. Start the engine.
Set the engine speed to 2500 min-1. Read the voltmeter reading when the generator output current is 10 A or less.
Analysis of results
If the voltmeter readings correspond to the nominal values \u200b\u200bof the regulated voltage given in the table, then the voltage regulator is working. If the voltmeter readings do not correspond to the range of nominal values, then either the voltage regulator or the generator is faulty.
After completing the check, gradually reduce the engine speed to idle, then turn off the ignition.
Disconnect the wire from the negative (–) battery terminals.
Disconnect the ammeter, voltmeter and reference tachometer.
Connect the standard wire to the output «IN» generator.
Connect the wire to the negative (–) battery terminal.