Kia Forum banner

1 - 3 of 3 Posts

·
Memorial Super Moderator
Joined
·
2,861 Posts
Discussion Starter #1 (Edited)
Checking an alternator. Start with a fully charged battery.

1. Switch on all lights for 5 minutes to reduce the charge in the battery and apply a load to the circuit.

2. Start the engine and bring revs to around 2500. An amp reading across the battery terminals should be around 75% of the alternators rated output.

3. Switch off all lights and run the engine at 1500-2000 revs until the indicated charge is below 10 amps. A volt reading should now be between 14 and 15 volts.

If the voltage reading is above 15 or below 14 the alternators voltage regulator is faulty.
 

·
Registered
Joined
·
42 Posts
Warning: Do not connect the ammeter across the battery terminals!! That is a dead short and can cause your battery to explode! The correct connection of an ammeter is in series with the circuit under test. In this case, it should be between the battery + terminal and the large wire that comes out of the alternator. The ammeter should be able to handle 75 or more amperes.

The correct connection of the voltmeter should be across the battery terminals.
 
1 - 3 of 3 Posts
Top