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Meter setup to check battery charge state:
•
Set the rotary switch to voltage ( ) setting.
•
Press the “
DC/AC
” button until “ ” appears on the display.
•
Insert the black lead in the “
COM
” jack.
•
Insert the red lead in the “
” jack.
Turn the headlights on for 30 seconds to dissipate any battery surface charge.
Disconnect the negative (-) battery cable from the negative battery terminal.
Connect:
•
Black test probe to the negative (-) battery post.
•
Red test probe to the positive (+) battery post.
Press the “
REC
” button (selects the MAX.MIN.AVG function).
A minimum reading of less than 12.4V indicates an undercharged battery. Recharge before further testing.
No Load 12V Battery Test
Meter Reading
% Battery Charge
12.60V or greater
100%
12.45V
75%
12.30V
50%
12.15V
25%
Note:
This table is only for non-critical reference.
Battery Parasitic Load Test
Each vehicle has a certain amount of parasitic load that is considered normal, but any current drain that
exceeds that amount should be located and stopped. On newer vehicles after the introduction of electronic
ignition and computer control systems, the parasitic load can be as high as 100mA. Check the manufacturer’s
specifications for the acceptable level of parasitic load for a specific vehicle.
WARNING
DO NOT CRANK THE ENGINE OR TURN ON ACCESSORIES THAT DRAW MORE THAN 10A COMBINED
DURING THIS TEST SINCE YOU COULD DAMAGE THE METER OR INJURE YOURSELF.
CAUTION
THE IGNITION SWITCH MUST BE OFF WHEN CONNECTING OR DISCONNECTING BATTERY CABLES TO
PREVENT DAMAGE TO THE VEHICLE COMPUTER.
