1999 AUDI A4 battery

The electrolyte level must reach the internal
electrolyte level indicator (lip of plastic flange).
This corresponds to the external maximum line
on the battery case.
Pa
ge 9 of 29 Batter
y
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.EE01.27.1

27-9

Electrolyte level too low

Special tools, test equipment and auxiliary
items
VAS5045 battery cell filler

Note:
If the electrolyte level is too low, the plates will
dry out causing a loss of capacity (power loss) in
the battery. If the plates are not surrounded by
electrolyte (sulfuric acid), the plates, plate straps
and the cell connectors will corrode. The result of
this corrosion is that battery function can no
longer be assured. The battery is made useless.

Notes: - If electrolyte level is too low, add distilled water up to maximum mark
using VAS5045 battery cell filler.
The design of the filler nozzle of the VAS5045 battery cell filler
prevents overfilling the battery cell and loss of battery acid. When the
maximum fill level is reached, the flow of distilled water into the battery
cell is stopped. To avoid contaminating the electrolyte, add only distilled water to the
battery (contaminated water will lead to increased self-discharge).
Pa
ge 10 of 29 Batter
y
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.EE01.27.1

27-10

Electrolyte level too high

Special tools, test equipment and auxiliary
items

Commercially available hydrometer
Note:
If the electrolyte level is too high, the sulfuric acid/water mixture will leak
to the outside of the battery and damage functional components in the
engine compartment.
- If electrolyte level is too high (overfilling), i.e., it is above internal
electrolyte level mark (lip of plastic flange) or external maximum line,
draw off excess electrolyte using commercially available hydrometer.
- Draw off electrolyte using hydrometer until electrolyte level has
reached lip of plastic flange or maximum line.
Pa
ge 11 of 29 Batter
y
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.EE01.27.1

27-12

No-load voltage, checking


CAUTION!

Battery cell caps must be screwed in tightly
when charging, measuring voltage or
performing load tests.
Always comply with the following
instructions otherwise a correct
measurement cannot be assured.

Special tools, test equipment and auxiliary
items
VAG1715 multimeter or
VAG1362 minitester or
Multimeter (Fluke 83 or equivalent)

Notes:
When testing the no-load voltage of a battery
installed in a vehicle, make sure the battery
Ground (GND) strap is disconnected.
The battery must not have been under a load
Pa
ge 13 of 29 Batter
y
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.EE01.27.1

for at least two hours before the test.
The battery must not have been charged at
least two hours before the test.
Pa
ge 14 of 29 Batter
y
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.EE01.27.1

27-13
Use the following procedure for testing the
voltage of a battery which is not under load:

- Switch ignition off.

- Disconnect battery Ground strap.

- Measure voltage between battery terminals.


12.5 volts or higher: battery OK

Below 12.5 volts: recharge battery
immediately Page 27
-21

Pa
ge 15 of 29 Batter
y
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.EE01.27.1

27-14

Specific gravity, checking


Special tools, test equipment and auxiliary
items

CAUTION!
Notes:
The specific gravity can be tested immediately after charging the battery.
Commercially available hydrometerShop towelWhen working with battery acid, make sure to follow all "Warnings
and safety precautions for lead-acid batteries." Wear suitable
protective clothing and eye protection. When disposing of batteries, always comply with applicable
Federal, State and local laws regarding the disposal of batteries
and sulfuric acid. In order to better determine the overall condition of a battery, always
perform a specific gravity test in conjunction with the load test. The temperature of the electrolyte must be at least 10 C (50 F).
Pa
ge 16 of 29 Batter
y
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.EE01.27.1

27-15
Use the following procedure to test the specific
gravity in all of the battery cells:

- Switch ignition off.

- Remove all cell caps.

The higher the specific gravity of the drawn electrolyte, the higher the
indicator will float.
The specific gravity of the electrolyte can be read in kg/dm3 on the
hydrometer scale. - Immerse tip of hydrometer into battery cell and draw out enough
electrolyte to allow indicator to float freely.
- Compare measured value indicated on hydrometer to values indicated
in table below:
Pa
ge 17 of 29 Batter
y
11/20/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.EE01.27.1