Useful information

HOW TO TEST IF YOUR CAR BATTERY IS FLAT

Do you remember when you last had your car battery checked? The summer heat and winter cold take a big toll on your car’s battery, which could wind up leaving you stranded.

If it’s been a while, or it has been a rough season for your battery, now is the time to have it tested.

Avoid testing the battery directly after the car has been driven, since surface charge in the battery might give erroneous voltage readings and you might then think the battery is OK, when in actual fact it is not. Rather let the vehicle stand for a while before testing or run some of the larger electrical consumers like lights or heating blower for a couple of seconds, to get rid of surface charge.

Select the DC voltage measurement function on your multimeter, then consult the user manual for instructions.

  • If your multimeter does not have an auto-ranging function, select the 20V DC (Test one battery only)
  • Touch the red probe to the positive terminal, and the black probe to the negative terminal.

The resting voltage should ideally be no lower than 12.6V. When a battery goes down to 12.2V, it’s actually only 50% charged, and below 12V it’s classed as discharged!

If you measure less than 12.6 volts, use a Smart Charger to charge the battery, without disconnecting it, to avoid any risk to the vehicle electronics.

When not using a Smart charger, remember that disconnecting a battery without a slave battery in place is not advised, as modern cars may lose memory settings.

If in doubt, always refer to the instruction manual.

Battery analysers are recognised worldwide as the standard for determining battery condition and provide a host of benefits:

  • Quick & accurate battery diagnosis.
  • Savings on time and money with improved testing productivity.
  • Increased customer turnaround times.
  • Reduced incidents of invalid warranty claims.
  • Improved customer satisfaction.
  • Fast, accurate test results on suspect batteries.
  • A printout of results for the customer.
  • Indicating when to replace weak batteries before they fail.
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