Charging System Performance Test

NOTE: In order to check the charging system, the use of a VAT-40 tester or equivalent is suggested.

1. Connect the VAT-40 or equivalent to the battery positive and negative posts.
2. Connect the current probe to the alternator + output lead to measure alternator output.
3. When measuring alternator output, the VAT-40 or equivalent can also be connected to the battery positive or negative cable. In this case, all electrical accessories must be turned off and 10-15 amps added to the reading on the VAT-40 or equivalent due to the engine operation.
4. With the engine running at 2000 rpm, adjust the VAT-40 or equivalent load bank to determine the output of the alternator. The alternator output should be near to, or exceed the alternator rating at 80°F ambient temperature.