Brand: OptiMATE Battery Chargers
Save a trip to the parts store (or a tow to the dealership) and test your electrical system yourself! The palm-sized OptiMate Test Cranking and Alternator Tester is an easy-to-use, 3-step tester with 18 LEDs to indicate the condition of your battery and charging system.
First, connect the tester to see the resting voltage level of your battery.
Next, start the vehicle to see the lowest cranking voltage. (The display will show the lowest voltage for 20 seconds.)
Finally, run the vehicle to check that the charging voltage is in the proper range for either lead-acid or lithium (LiFePO4) batteries.
The OptiMate Test measures just 3" Wide x 2 1/2" High x 1" Thick, small enough to keep in your glovebox so you never have to worry. The short 10" pigtail cord on the Test unit has the same 2-pin SAE connector as on all OptiMate battery chargers, so you can plug it right into your Optimate charging harness. It also includes a 34" long cable with alligator clamps for use on vehicles without a charging harness. Full instructions and recommendations are printed right on the back of the unit.
A simple 15-second test with this inexpensive tool can save you from being stranded on a road trip. It can also save you from mistakenly replacing a battery (or alternator) that doesn't need replacement! Buying a used vehicle? Bring it along and find out if the battery is really new, or if you might not make it home. Works with all 12 volt (nominal) automotive and powersports batteries, including conventional lead-acid, AGM, gel cell, and lithium (LFP / LiFePO4).