1, LED display indicates condition 2, when red light is lit, charging is complete. 3,12 V Digital Battery Tester

1, LED display indicates condition 

2, Charger check: when red light is lit, charging is complete.

3, Alternator check : accelerate your engine to 2000 rpm when the red light is lit ,charging circuit is ok.

4, Battery check: indicate the percentage charging in the battery .

5, Cranking check : red light must remain lit when starter motor operates.

6, 12 V Digital Battery Tester

12V LED Digital Battery Load Tester