volkswagen Workshop Repair Guides

Volkswagen Workshop Service and Repair Manuals

ABOUT US
Charging battery > < Deviations in electrolyte density

Passat (B3)

Battery load test
Battery load test
  WARNING
Ensure that following notes are observed otherwise correct measurements can not be guaranteed.
When disposing batteries it is absolutely necessary that the disposal procedures for batteries and sulphuric acid are observed.
The electrolyte specific gravity test in conjunction with the battery load test provides specific information of the battery condition.
Special tools and workshop equipment required
   
t  Battery tester -VAS 1979- or-VAS 5033-
t  Observe accident prevention procedures, wear protective clothing i.e. protective goggles/visor and leather gloves.
  Note
The load current varies and must be set on the tester according to battery capacity.
Performing battery load test
–  Battery must be removed from vehicle → Chapter.
–  The battery load test should be carried out using battery tester -VAS 1979- or -VAS 5033-.
–  Important: Connect the clips to battery terminal as described in the tester instruction manual. The clips must make good contact with the battery terminals.
–  The load current varies and must be set on the tester according to the battery capacity, this can be taken from the following table → Anchor.
–  The minimum voltage varies, the value must not fall below this, and can be taken from the following table.
The load current and the minimum voltage varies depending upon the capacity of the battery and should be taken from the following table.
Table:
  N27-0082
Battery capacityLow temperature test currentLoad currentMinimum voltage (limit value)
36 Ah175 A100 A10.0 V
40 Ah - 49 Ah220 A200 A9.2 V
50 Ah - 60 Ah265 A - 280 A200 A9.4 V
61 Ah - 80 Ah300 A - 380 A300 A9.0 V
81 Ah - 110 Ah380 A - 500 A300 A9.5 V

Characteristics after successfully completing battery load tests
t  The battery voltage lowers (high current flow) caused by the high load (ohmic resistance) during this test. If a battery is in working order the battery voltage will only drop to the lowest voltage. This varies and is dependent upon the battery capacity and the low temperature test current. Low temperature test current is understood to mean a battery power in the colder periods of the year. Batteries with a high low temperature test current are specially important for vehicles with high compression engines.
t  If the battery is defective or has a lower charge state the battery voltage drops very quickly “voltage collapses” to a voltage below 9.0 V. After the test is completed, these low voltage values remain over a longer period, and the voltage increases very slowly again. A usable voltage value (no load voltage) → Chapter is no longer reached with such a battery.
t  A battery with such faults must be noted as it no longer has the reserves of an undamaged battery.
t  A battery with such a fault must be disposed of.
   

Charging battery > < Deviations in electrolyte density