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Volkswagen Jetta / Bora: Electrical System Manual - part 7

INFO

In the display the symbol -1- for “service charge for wet batteries”

or the symbol -2- for “service charge for gel/absorbent glass mat

batteries” will appear.
– Set battery capacity (Ah) of battery for charging using respec‐

tive button “Up”

↑

or “Down”

↓

– Connect red terminal clamp “+” to positive terminal on battery.
– Connect black terminal clamp “-” to negative terminal on bat‐

tery.

– Press

START / STOP

for approx. 5 seconds. The menu

““charging totally discharged batteries/support mode” will be

activated.

– Press respective button “Up”

↑

or “Down”

↓

to set the respec‐

tive battery voltage (6 V, 12 V or 24 V).

Note

If a button is not pressed within 5 seconds the charger will return

to the main menu (select operating mode).

– Confirm the selected battery voltage with

START / STOP

Then follows the enquiry for "is charger cable terminal polarity

correct".
– Check polarity of charger unit cables.
– Confirm polarity of charger unit cables with

START / STOP

Charger will start charging sequence for totally discharged bat‐

tery.
Ending battery charging sequence:
– Press

START / STOP

– Disconnect black terminal clamp “-” of charger unit from neg‐

ative terminal on battery.

– Disconnect red terminal clamp “+” of charger unit from nega‐

tive terminal on battery.

– Pull charger unit plug out power supply socket.

3.2.5

Charging battery in support mode with

battery charger -VAS 5900-

WARNING

Danger of injury! Observe warning notices and safety regula‐

tions

⇒ page 2

Jetta 2005 ➤ , Bora 2006 ➤

3. Charging battery

♦ The terminal polarity protection in operating mode “charg‐

ing totally discharged batteries/support mode” is not ac‐

tive. Connect battery charger terminal clamps correctly to

battery terminals.

♦ When charging in support mode always set the battery

charger to the correct type of battery ⇒ Operating instruc‐

tions for battery charger -VAS 5900- !

♦ Do not press

START / STOP

button when charger unit

cables are connected incorrectly. The charger unit may be

damaged.

When in support mode the battery charger -VAS 5900- replaces

a defective vehicle battery whilst it is being exchanged. The on‐

board supply remains intact. The vehicles electrical equipment

(e.g. electric windows) can be used.
Special tools and workshop equipment required
♦ Battery charger -VAS 5900-

– Switch off the ignition and all electrical consumers.
– Connect charger unit plug to power supply. The last selected

operating mode will appear on display

⇒ page 19

– Press

START / STOP

for approx. 5 seconds. The menu

““charging totally discharged batteries/support mode” will be

activated.

– Press respective button “Up”

↑

or “Down”

↓

to set the re‐

spective onboard supply voltage (6 V, 12 V or 24 V).

Note

If a button is not pressed within 5 seconds the charger will return

to the main menu (select operating mode).

– Confirm the selected battery voltage with

START / STOP

– Connect red terminal clamp “+” of charger unit to positive ter‐

minal of vehicle.

– Connect black terminal clamp “-” of charger unit to negative

terminal of vehicle.

Then follows the enquiry for "is charger cable terminal polarity

correct".
– Check polarity of charger unit cables.
– Confirm polarity of charger unit cables with

START / STOP

Jetta 2005 ➤ , Bora 2006 ➤

⇒ page 31

– Press

START / STOP

. The support mode is terminated.

– Disconnect black terminal clamp “-” of charger unit from neg‐

ative terminal of vehicle.

– Disconnect red terminal clamp “+” of charger unit from positive

terminal of vehicle.

– Pull charger unit plug out power supply socket.

3.2.6

Charging battery in maintenance mode

with battery charger -VAS 5900-

WARNING

Danger of injury! Observe warning notices and safety regula‐

tions

⇒ page 2

When the battery is fully charged the battery charger -VAS 5900-

switches to maintenance mode.
– Proceed as for charging battery

⇒ page 19

At a charge condition of 100 % all bars appear in display.

Note

♦

When a battery is being charged in the buffer mode and a

consumer draws current from the battery, the battery charger

-VAS 5900- automatically compensates the charge.

♦

The maintenance mode can be continued for an unlimited pe‐

riod.

♦

The battery is always ready for use.

♦

Observe battery manufacture's maintenance instructions!

3.3

Totally discharged batteries

WARNING

Danger of injury! Observe warning notices and safety regula‐

tions

⇒ page 2

A battery is designated “totally discharged” when the "no load"

voltage is less than 12.2 V.

Caution

♦ Totally discharged batteries freeze prematurely.
♦ Frozen batteries should no longer be used.

Jetta 2005 ➤ , Bora 2006 ➤

3. Charging battery

♦

Batteries that have not been used for a long time e.g. vehicles

that have been stored, will self-discharge.

♦

In totally discharged batteries, the electrolyte is comprised al‐

most entirely of water because the acid content is so low.

♦

Totally discharged batteries sulphate, that is, the entire plate

surfaces of the battery harden.

♦

If a battery is recharged shortly after it has totally lost its

charge, the sulphation will dissipate.

♦

If these batteries are not recharged the plates continue to

harden and the ability to recharge is reduced. A reduction in

the battery output is the result.

– Check no load voltage of battery

⇒ page 15

– Charge battery.
Charging battery with battery charger -VAS 5095 A-

⇒ page 15

Charging battery with battery charger -VAS 5900-

⇒ page 19

Jetta 2005 ➤ , Bora 2006 ➤

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