The battery condition is a measure of the batterys ability to accept and maintain a good charge. A battery in
poor condition may be able to be fully recharged. However, a battery in poor condition with a full charge will
lose its charge more quickly than a battery in good condition with a full charge. If a battery fails the battery
condition evaluation, then the battery should be replaced.
The procedures for testing batteries are listed on three battery test cards. Each card describes procedures for
evaluating different combinations of batteries:
Complete battery pack
Series pair of batteries
B A T T E R Y P A C K S
A battery pack is the combination of four of more batteries in a particular circuit of a vehicle/equipment, i.e.
the starting circuit. Testing the batteries in a pack evaluates the general condition of the pack as a whole.
Note, the results of a battery pack test may be misleading. A single battery from a pack of four may be bad
even though the pack as a whole may pass the tests. This can happen if the other three batteries in the pack
are in very good condition. In order to test a battery pack, the current probe must be clamped around a single
cable carrying all of the starter current. If such a connection cannot be made, then test each pair of batteries
S E R I E S P A I R S
A series pair is one in which the negative terminal of one battery is connected by a cable to the positive
terminal of another battery. This test configuration should be used when any of the following conditions exists:
There are only two batteries (one series pair) in the vehicle/equipment.
An evaluation of the pack is desired, but the current probe cannot measure the total starter
current. This condition can occur if the cable is not readily accessible or if the cable is physically
The battery pack test has failed, and the user wants to further identify any bad battery pair.
Note, testing each series pair yields a better evaluation than testing the pack as a whole.
I N D I V I D U A L B A T T E R I E S
An individual battery test refers to the process of testing one battery at a time. The battery could be part of a
pack, a series pair, or a single battery. Test the batteries individually if a battery series pair failed the tests
and it is desired to isolate to a single battery (or if there is only one battery in the circuit). Testing individual
batteries gives the best evaluation.
D E S C R I P T I O N O F T E S T C A R D S
The front of each test card has three sections. The top of the card explains how to connect the VTM to the
batteries being tested. The middle part of the card describes the procedure to follow in order to evaluate the
batteries. The bottom of the card contains illustrations showing typical vehicle hookups.