Checking voltage under load — AUDI

Warning:
Ensure that following notes are observed otherwise correct check cannot be guaranteed.
When disposing of batteries it is absolutely necessary that disposal procedures for batteries and sulphuric acid are observed.
In conjunction with "voltage under load" test, electrolyte density test gives a good indication of battery condition.

Special tools, testers and auxiliary items required

Battery tester VAS 1979 or VAS 5033
Observe accident prevention procedures, wear protective clothing i.e. protective goggles and leather gloves.

Note:

The load current will vary depending on battery capacity and must be set on tester accordingly.

Performing battery load test

The battery load test should be carried out using battery tester VAS 1979 or VAS 5033.
The battery load test should be carried out using battery tester VAS 1979 or VAS 5033.
Battery must be removed from vehicle => Page
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.
Very important:
Connect clips to battery terminals as described in operating manual of tester. The clips must make good contact with battery terminals.
The load current varies depending on battery capacity, and must be set on tester accordingly: =>Operating manual of battery tester.

The load current can be taken from table below.
The voltage reading obtained under test must not be less than minimum voltage listed in table below.
The load current and minimum voltage vary depending on battery capacity.

Table:

Battery capacity · Low temperature test current · Load current · Minimum voltage (limit value)
36 Ah · 175 A · 100 A · 10.0 V
40 Ah · 220 A · 200 A · 9.4 V
50 Ah · 265 A · 200 A · 9.6 V
63 Ah · 300 A · 200 A · 9.5 V
88 Ah · 395 A · 300 A · 9.5 V
92 Ah · 450 A · 300 A · 9.5 V

Characteristics after successfully completing battery load tests

The battery voltage lowers (high current flow) caused by high load (resistance) during this test. If a battery is in working order battery voltage will only drop to lowest voltage. This varies, and is dependent upon battery capacity and low temperature test current. Low temperature test current is understood to mean a battery power in colder periods of the year. Batteries with a high low temperature test current are especially important for vehicles with high compression engines.
If battery is defective or is in a low charge state, battery voltage will drop quickly "voltage break up", i.e. voltages below 9.0V (Volt). After completing test these low voltage values remain over an extremely long period, voltage increases very slowly again. A usable voltage value (no load voltage) => Page
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is no longer reached with such a battery.
A battery with such faults must be noted as it no longer has the reserves of an undamaged battery.
A battery with such a fault must be disposed of.