Generator Voltage Drop Test
1. The test is performed on a warm engine.
2. Connect the tachometer, start the engine and turn on all powerful consumers (heater fan, high beam headlights, etc.).
3. Bring the speed up to 2400 rpm and without changing the speed, do the following.
4. Check the voltage between the (+) battery terminal and the stud (not with a nut!) terminals B+ of the generator, which should not be higher than 0.6 V. If the voltage is higher than 0.6 V, then touch the nut and the tip of the wire on the generator. If the voltage drops below 0.6 V, this indicates poor contact in the connection. In this way, any section of the circuit can be checked if there is a suspicion of a connection fault.
5. Check the voltage between the (-) battery terminal and the ground connection stud on the generator housing, which should not be higher than 0.3 V. If the voltage is higher than 0.3 V, touch the nut and the wire tip on the generator. If the voltage drops below 0.3 V, this indicates poor contact in the connection.
Checking the generator output voltage
To perform this test you need to have a VAT-40 automotive tester (or equivalent) complete with rheostat and current transformer.
1. Check the battery charge level and belt tension.
2. Check the contacts in all connections for voltage drop (see above).
3. Warm up the engine.
4. Connect the VAT-40 tester according to the instructions.
5. Start the engine and increase the speed to 3000 rpm (all consumers must be disconnected). After turning on the fan, let the engine idle for 15 minutes.
6. Increase the speed to 2000 rpm. The voltage should not be higher than 15.1 V. Otherwise, check the charging current with the current transformer that covers the terminal B wire on the generator.
7. To do this, increase the speed to 2000 rpm. The voltage should not be lower than 13.5 V. Otherwise, replace the generator.
8. Connect the tester's equivalent load and set the current so that the voltage drops to 12-13.5 V. If the charging current is less than 75 A, check the voltage regulator and the generator in the full excitation mode of the generator. To do this, insert the probe from the tester kit into the hole in the rear cover of the generator and bring the engine speed to 2000 rpm. If the current is more than 65 A (CR-V) or 75 A (Odyssey), replace the voltage regulator; if it is less than the specified values, replace the generator.
[Publication reprinted from the website www.hondabook.ru]