VOLKSWAGEN BORA 1999 (02) PDF Document

The VOLKSWAGEN BORA 1999 uses two main types of maintenance-free batteries:

Battery with magic eye:

This is a maintenance-free wet battery with liquid electrolyte. It is equipped with a “magic eye” that provides information about the electrolyte level and the charge state through a colored display. You should not remove any stickers or replenish it with distilled water; only a visual check is needed. Note: Batteries where the magic eye is colorless or light yellow must not be checked or charged and must be renewed. Do not attempt to jump start the vehicle as there is a danger of explosion.

Absorbent glass mat (AGM) battery:

This is a maintenance-free lead-acid battery where the electrolyte is contained within a microscopic glass mat. It is sealed and fitted with valves. AGM batteries are identified by the abbreviation “AGM” on the battery and may not have a magic eye. When replacing an AGM battery, it must always be replaced with another AGM battery.

When handling the battery in your VOLKSWAGEN BORA 1999, observe the following safety precautions:

Personnel and Supervision:

Untrained personnel should only work on batteries when supervised by a qualified vehicle mechanic or electrician.

Corrosive Acid:

Battery acid is highly corrosive. Always have a neutralizing solution (e.g., soap solution) available to treat acid burns. Leaking electrolyte can cause skin burns and corrosion on the vehicle.

Explosive Gas:

Batteries produce explosive gas when charging. A battery may explode if not handled correctly. Do not check, charge, or jump-start batteries where the magic eye is colorless or light yellow.

Sparks and Flames:

It is prohibited to cause sparks (through grinding, welding, etc.) or use naked lights near batteries. Smoking is also prohibited. Avoid sparks from electrostatic charging by touching the vehicle body before touching the battery.

Working Environment:

Only work on batteries in well-ventilated and suitable rooms.

Protective Gear:

Always wear eye protection and gloves when working with batteries. Do not tilt the battery, as acid can leak from the gas vents.

Tools and Short Circuits:

Never lay a tool on a battery to avoid short circuits.

Children:

Keep children away from acid and batteries.

To prevent damage to the battery clamps and terminals on your VOLKSWAGEN BORA 1999, please follow these guidelines:

• The battery clamps should only be fitted by hand and without using force.

• Battery terminals should not be coated with grease.

• The battery clamps should be fitted so that the battery terminal is either flush with the clamp or protruding from it.

• Once the battery clamps have been tightened to the specified torque, the threaded connections should not be tightened any further.

To check a battery with a magic eye in your VOLKSWAGEN BORA 1999, carry out the procedure in the following sequence:

1. Perform a visual check of the battery’s external condition, terminals, and mounting.

2. Check the color display of the magic eye. There are two types:

• “3-colour” magic eye

• “2-colour” magic eye

WARNING: Batteries where the magic eye is colorless or light yellow must not be checked or charged. Do not jump-start the vehicle. These batteries must be renewed.

3. Perform a battery load test using a battery tester such as VAS 5097 A or VAS 6161.

4. Depending on the result of the battery test, you may need to perform a current draw test.

To check an AGM battery in your VOLKSWAGEN BORA 1999, follow this sequence:

1. Perform a visual check for any damage to the housing or terminals and ensure it is securely mounted.

2. Perform a battery load test using a battery tester with a printer, such as the VAS 5097 A or VAS 6161. These testers have specific settings for AGM batteries.

3. Depending on the test result, a current draw test may be necessary.

A visual inspection of the battery in your VOLKSWAGEN BORA 1999 is essential to check its external condition, terminals, and proper attachment before performing extensive tests. This inspection helps to establish:

• If the battery housing is damaged: A damaged housing can leak electrolyte (battery acid), which can cause serious damage to vehicle components. If acid has leaked, treat affected components immediately with an acid neutralizer or a soap solution.

• If the battery terminals are damaged: Damaged terminals can prevent a good connection with the battery clamps, leading to malfunctions in the electrical system or even burning wires. Ensure clamps are correctly seated and tightened to the specified torque.

• If the battery is secured correctly: The battery must be securely seated. Vibrations can shorten the battery’s life, damage the cell plates, and potentially damage the housing, creating an explosion risk. If necessary, tighten the securing bolt to the specified torque.

The “3-colour” magic eye provides information on the electrolyte level and charge state of the battery. Before checking, lightly and carefully tap the magic eye with a screwdriver handle to dissipate any air bubbles that could distort the display. The three possible colors indicate the following:

• »Green«: The battery is charged sufficiently.

• »Black«: The battery is partly discharged (charge state < 65%) or completely discharged.

• »Colourless or light yellow«: The battery must be renewed. Do not check, charge, or jump-start a battery showing this color, as there is a danger of explosion.

Note that the magic eye only reflects the condition of one battery cell. For an exact determination of the battery’s condition, a full battery load test is required.

For newer batteries, the »green« color display has been discontinued. This magic eye primarily indicates the electrolyte level. Before checking, lightly tap the magic eye to dissipate any air bubbles. The possible colors mean:

• »Black«: The electrolyte level is OK.

• »Colourless or light yellow«: The electrolyte level is too low. The battery must be renewed.

WARNING: Batteries where the magic eye is colorless or light yellow must not be checked or charged. Do not jump-start the vehicle. These batteries must be renewed due to the danger of explosion.

The charge state of these batteries cannot be read from the magic eye; a battery load test must be performed for this purpose.

To perform a battery load test with the VAS 5097 A tester, follow these steps. The battery must have a temperature of at least 10 °C.

1. Switch off the ignition and all electrical consumers.

2. For batteries with a magic eye, check the color. Do not test if it is colorless or light yellow.

3. Check the low-temperature test current in amperes (A) according to DIN on the battery label. If the values are in IEC or EN/SAE, use the conversion table.

4. Select the appropriate low-temperature test current on the tester using the selection switch.

5. Select the measuring range (80 – 379 A or 380 – 499 A) with the ON/OFF and functions switch.

6. Connect the red terminal clamp of the tester to the positive battery terminal and the black terminal clamp to the negative terminal. Ensure a good contact.

7. Select the connection point with the selection switch (1 for directly on battery, 2 for external test points).

8. Press the start test button. The green LED will light up, and the test will run automatically for about 20 seconds.

9. The test result will be printed out. If the unit does not start (no LED, no printout), the battery needs to be recharged.

10. Switch off the unit and remove the test terminals.

Note: Perform the test only once, as repeating it immediately will falsify the result. The tester needs approximately 30 minutes to cool down before the next test.

Here is the conversion table for cold cranking current in Amperes (A) between EN/SAE, IEC, and DIN standards for your VOLKSWAGEN BORA 1999 battery.

Based on the printout from the VAS 5097 A battery tester, take the following actions for your VOLKSWAGEN BORA 1999:

To perform a battery test with the VAS 6161 tester, follow these steps:

1. Switch off the ignition and all electrical consumers.

2. If applicable, check the magic eye on the battery. Do not test if it is colorless or light yellow.

3. Switch on the VAS 6161 unit.

4. Connect the red terminal to the positive battery terminal and the black terminal to the negative terminal. Ensure a good contact.

5. Select one of the following functions from the menu:

• Maintenance test: Used for new cars before registration or during stock maintenance.

• Service test: Used for regular service checks.

• Guarantee test: Used for warranty claims.

The specific steps for each test type will be displayed on the screen. Generally, you will need to select the connection point, battery type, and measure the temperature with the integrated sensor before starting the test. The test completes in about 10 seconds and the result is printed out.

The following tables explain the measures to be taken based on the results from the VAS 6161 tester for guarantee, service, and maintenance tests on your VOLKSWAGEN BORA 1999.

Evaluating battery test results for guarantee and service tests

Evaluating battery test results for maintenance test

A current draw test helps to quickly determine the state of a discharged battery. The test is performed while charging the battery.

Test Requirements:

• The battery temperature must be at least +10 °C.

• The charger must be capable of outputting a charge current of at least 30 A (e.g., VAS 5095A, VAS 5900, VAS 5903).

• A current pick-up clamp is required to measure the current draw.

Procedure:

1. Connect the battery to the battery charger.

2. Start the charging sequence.

3. Measure the charging current of the battery after 5 minutes.

Test Result:

• If the current draw (A) is higher than 10% of the nominal capacity (Ah): For example, > 6.1 A for a 61 Ah battery. The battery is likely serviceable. Fully charge the battery and then perform a standard battery test after allowing it to rest for two hours.

• If the charge current (A) is below 10% of the nominal capacity: For example, < 5A for a 50 Ah battery. The battery cannot take a charge and must be renewed.

To charge the battery with the VAS 5095 A charger, ensure the battery has a temperature of at least 10 °C.

1. Switch off the ignition and all electrical consumers.

2. On the base of the charger unit, check that the battery type change-over switch is set to 2.4 V/C (volts/battery cell). This applies to all batteries.

3. Connect the red terminal clamp of the charger to the positive terminal on the battery.

4. Connect the black terminal clamp of the charger to the negative terminal. For vehicles with a start/stop function, connect the black clamp to body earth to avoid system malfunctions.

5. Switch on the battery charger using the ON/OFF switch.

6. The yellow charging current indicators will light up. When only the LED for >90% charge is lit, the battery is almost full. When the green “maintaining charge” LED lights up, the battery is fully charged.

7. Switch off the charging unit.

8. Remove the charger terminals from the battery terminals.

To activate or deactivate the cruise control system using a vehicle diagnostic tester, follow these steps:

1. Connect the vehicle diagnostic tester to your VOLKSWAGEN BORA 1999.

2. Select the “Guided fault finding” mode on the tester.

3. Using the “GoTo” button, select “Functions/component”.

4. Select the following menu options in sequence:

• Drive

• Engine code

• 01 – On Board Diagnostic capable systems

• Engine management/diesel direct injection and glow plug system

• Functions

• Activating and deactivating cruise control system (CCS)

Your VOLKSWAGEN BORA 1999 may have different types of hose couplings for the washer system. Here is how to handle them:

Type 1 (Simple Push-Fit):

• To loosen: Pull the two coupling sections apart.

• To secure: Push the two sections together until you hear and feel them engage.

Type 2 (Rotating Lock Ring):

• To loosen: Rotate the lock ring through 90° and pull off the hose connection.

• To secure: Push on the hose connection and rotate the lock ring until it engages.

Type 3 (Lifting Lock Ring):

• To loosen: Pull up the lock ring by approximately 1 mm and pull off the hose connection.

• To secure: Attach the hose connection and press in the clip until it engages.

Headlight Washer System Coupling:

• To loosen: Push the lock ring and pull off the hose connection.

• To secure: Push and hold the lock ring while pushing on the hose connection. Check that it is secure by trying to pull it off without depressing the clip.

To repair a smooth washer pipe with a diameter of 5×1 mm or 6×1 mm, you can use a special EPDM hose.

1. Cut the damaged section out of the smooth pipe at right angles.

2. Select the appropriate EPDM hose and cable ties from the electronic parts catalogue.

3. Cut a length of EPDM hose so that the ends of the original smooth pipe can each be pushed about 10 mm into the EPDM hose.

4. Secure both repair joints with cable ties.

To repair a damaged corrugated washer pipe, you will need end pieces, shrink-fit piping, and a hot air blower.

1. Cut the damaged section out of the corrugated pipe at right angles.

2. Select suitable end pieces and the correct sized shrink-fit piping from the electronic parts catalogue.

3. Heat one end of the corrugated pipe.

4. Push a connector into the heated end.

5. Repeat for the other end of the corrugated pipe with the other connector.

6. Cut a piece of heat-shrink hose so that it covers the repair joint and overlaps each end of the corrugated pipe by about 20 mm.

7. Push the heat-shrink hose over the corrugated pipe, join the connectors, and secure the repair by applying heat to the shrink hose.

Note: If the damaged section is longer than 20 mm, a new piece of corrugated pipe must be used to bridge the gap.

Working on gas discharge headlights involves lethally high voltage and other hazards. Always observe the following safety rules:

• Disconnect Power: It is absolutely necessary to disconnect the battery earth strap before working on any parts marked with yellow high voltage symbols.

• Discharge Residual Voltage: After disconnecting the battery, switch the dipped beam on and off again to eliminate any possible residual voltage.

• High Voltage: Control units, connectors, and bulb holder components conduct lethally high voltage (above 28,000 V on ignition). Never operate the control unit without a bulb fitted.

• Pressure and Explosion Risk: H7 bulbs and gas discharge bulbs are under pressure and can explode while being changed. This can cause injury.

• Protective Gear: Always wear protective goggles and gloves when removing and installing gas discharge bulbs.

• Heat: The glass of the bulbs can get very hot, creating a danger of burns.

• UV Radiation: Avoid looking directly into the beam, as the UV rays are about 2.5 times greater than from normal halogen bulbs.

• Operation: Gas discharge bulbs must only be operated inside the headlight housing.

• Familiarity: Never change bulbs if you are not familiar with the appropriate procedures, safety precautions, and tools.

To remove and install an illuminated cigarette lighter socket, you will need the special puller T 40148. Sockets without illumination usually cannot be removed without being damaged.

Removing:

1. Remove the cigarette lighter or dummy plug from the socket if present.

2. Push the puller (T 40148) into the socket so that its locking lugs engage in the recesses inside the socket.

3. Pull the grip on the puller to release the locking lugs of the socket’s retaining sleeve.

4. Pull the socket out of the retaining sleeve using the puller. Take care not to stretch the wiring.

5. Pull off the socket connector.

6. To release the puller from the socket, press the spindle on the puller and turn the puller briefly to the left.

Installing:

Install in the reverse order of removal.

Important: After removing the socket with the puller, the retaining springs inside the socket may be spread apart. Carefully press these springs back together and check that the cigarette lighter stays in position after its heating phase, ensuring it is not ejected from the vehicle interior.

Note that on some vehicles, illumination is provided by a non-replaceable LED. This procedure applies only to sockets with a replaceable light bulb.

1. Remove the cigarette lighter socket from its mounting location.

2. Press the retaining lugs on the side of the retaining sleeve and remove the sleeve together with the bulb carrier.

3. Unclip the bulb carrier from the retaining sleeve.

4. Separate the two parts of the bulb carrier (A and B) to access the bulb.

5. Open part B of the bulb carrier.

6. Remove the light bulb.

Installation:

Installation is carried out in the reverse order of removal.

To connect a diagnostic tester to your VOLKSWAGEN BORA 1999, follow these steps:

1. Apply the handbrake.

2. For automatic gearboxes, move the selector lever to “P” or “N”. For manual gearboxes, move the gear lever to the neutral position.

3. The diagnostic interface is located in the driver’s footwell area. You may need to pull out a trim piece to access it.

4. With the ignition switched off, connect the vehicle diagnostic tester using the appropriate diagnostic cable (e.g., VAS 5051/6A) to the diagnostic interface in the vehicle.

5. Switch on the ignition.

6. Switch off all electrical consumers before starting diagnosis.

When performing repairs on the vehicle electrical system and wiring harnesses, it is crucial to follow these rules to ensure safety and functionality:

• Disconnect the Battery: Always disconnect the battery earth strap before working on the electrical system.

• Identify the Cause: Before repairing, find and rectify the root cause of the damage (e.g., sharp edges, corrosion).

• No Soldering: Soldering is not permitted for repairs to vehicle wiring. Use approved crimp connectors.

• Use Repair Sets: Repairs should be carried out using the approved wiring harness repair set (e.g., VAS 1978 B).

• Mark Repairs: Wiring harness repairs should not be integrated back into the original harness loom. They must be marked with yellow adhesive tape to indicate a previous repair.

• Seal Connectors: After crimping, crimp connectors must be shrink-fitted using a hot air blower to prevent moisture ingress.

• Special Systems: Observe supplementary information for repairs to critical systems like airbags, belt tensioners, CAN bus lines, and fibre optic cables.

• Function Test: Carry out a function test after every repair. It may be necessary to interrogate and erase the fault memory.

• Screened Wires: Screened wires must not be repaired. If damaged, they must be replaced completely.

• Heat Resistant Wiring: In areas like the engine compartment, only use heat-resistant wiring for repairs.

Due to the critical safety function of the airbag and seat belt tensioning system, repairs to its wiring must follow strict guidelines:

• Use Approved Parts: Only use contacts, connectors, and wiring specifically designed for this purpose, available from the electronic parts catalogue.

• Repair Limit: A maximum of two repairs are permitted on the wiring for the airbag and belt tensioner system. More repairs increase resistance and can trigger faults.

• Proximity to Connectors: Repairs should be no more than 30 cm from the next contact housing.

• Entwined Wires: The wires to the triggering units are twisted (entwined) as a pair. This twisting must be maintained in the repaired section. The standard twine spacing is 20 mm ± 5 mm. There must not be any untwisted section longer than 100 mm.

• Wire Length: During repairs, both wires in a pair must have the exact same length.

• Marking: Clearly mark the area of repair with yellow insulating tape.

CAN bus wiring is an unshielded two-wire line (CAN-High and CAN-Low). To ensure proper communication, repairs must adhere to these rules:

• Wire Type: Use the correct cross-section (0.35 mm² or 0.5 mm²) and color-coded wires for the specific CAN system (Powertrain, Convenience, or Infotainment).

CAN Bus Wiring Colour Codes:

• Equal Length: When repairs are performed, both bus wires (CAN-High and CAN-Low) must have the same length.

• Twisting: When twisting the wires together, the length of each complete twist must be 20 mm.

• Untwisted Sections: There must not be any section of wiring (e.g., near crimp connectors) longer than 50 mm where the wires are not twisted.

• Marking: Mark the area of repair with yellow insulation tape to make it easy to identify.

To release and dismantle contacts from housings, you must use the correct release tools to avoid damage.

1. Secondary Locking Element:

• Many housings have a secondary lock, which is a colored catch or flap that secures all wires at once. This must be opened or removed first. This can be done by removing a toothed element, opening a flap, or detaching a slide, depending on the connector type.

2. Primary Locking Element (Releasing the Individual Contact):

• The primary lock is what holds an individual crimp contact in place.

• Identify the correct release tool for the specific contact type (e.g., round, flat, special).

• Insert the release tool into the appropriate release port on the contact housing.

• Gently push the contact’s wire further into the housing. This action, combined with the release tool, lifts the locking tabs of the contact off the housing edge.

• While pushing the release tool, pull the wire to remove the contact from the housing.

• Remove the release tool once the contact is out.

Important: Never pull the contacts out of the housings by force without using the correct release tool. Damaged contact housings must always be replaced.

To ensure optimal electrical contact, ring terminals and their threaded connection points must be clean and free of corrosion. Use a contact surface cleaning set like VAS 6410.

Repairing a Ring Terminal:

1. Disconnect the battery.

2. Loosen the nut and remove the ring terminal from the threaded connection.

3. Check the terminal for corrosion and dirt.

4. Select a suitable adapter and sanding pad (grey for light dirt, red for heavy dirt).

5. Insert the adapter into the ring terminal and grind off corrosion with circular movements. Be careful not to abrade the tin coating excessively to the point where copper is visible.

6. If necessary, remove any punching burr with a deburrer.

Repairing a Threaded Connection:

1. After removing the ring terminal, check the threaded connection point (stud) for corrosion.

2. Select a suitable adapter and sanding pad.

3. Set the adapter on the threaded connection and clean off corrosion and dirt with circular movements.

Final Steps:

1. Re-attach the ring terminal and tighten the nut to the specified torque.

2. Apply a suitable anti-corrosion treatment.

3. Reconnect the battery and teach-in any systems as required (e.g., electric windows, radio code).

Lambda probe wires should not be repaired. If a probe is faulty, it must be replaced. The procedure is similar for 4-pin (LSF) and 6-pin (LSU) probes.

1. Remove the defective Lambda probe from the exhaust system.

2. Place the new uniform probe and the old defective probe next to each other, aligning the sensor housings so they are at the same height.

3. Tie back any excess length in the new probe’s wire (approx. 50 – 250 mm) to match the length of the old probe’s wire. Secure the excess with cable ties.

4. Check that the connector housing of the new probe is compatible with the connector on the vehicle’s onboard supply side. On older vehicles, it may be necessary to replace the vehicle-side connector with the one supplied with the new probe.

5. If replacing the connector, observe the pin assignment. The pins in the new connector housing are color-marked for clarity.

6. Install the new Lambda probe into the vehicle and tighten it to the specified torque.