Generators & Regulators Audi A4 B6

DESCRIPTION

Bosch alternators are conventional 3-phase, self-rectifying type alternators. Bosch voltage regulators are transistorized and integral with alternator. Manufacturer recommends replacing generator as an assembly.

BELT TENSION

Serpentine belt tension is automatically adjusted by tensioner.

DRIVE BELT ROUTING

Note. Serpentine belt is self-adjusting. For drive belt routing (Scheme 1)or (Scheme 2).

Scheme 1

Scheme 2

PRELIMINARY INSPECTION

Verify customer complaint by operating system. Visually inspect for obvious signs of mechanical and electrical damage. Check generator belt tension and condition. Ensure that battery voltage is within specifications. Following manufacturers instructions for load tester, load test battery. See LOAD TEST under ON-VEHICLE TESTING. Inspect for blown fuses and damaged relays. For fuse and/or relay identification, see WIRING DIAGRAMS . Verify ground connection integrity between engine, body, battery and generator. Check for damaged wiring harnesses and/or switches. Check for a broken or partially broken wire inside insulation, which could cause system malfunction but prove good in a continuity/voltage check with system disconnected. Ensure any aftermarket electronic equipment is properly installed. If fault is found, repair as necessary. If no fault is found, check for conditions that might cause an intermittent situation.

LOAD TEST

Turn ignition to OFF position. Connect tester cable clamps to battery terminal. Ensure clamps have a good contact with battery terminals. Connect battery tester according to tool manufacturer's instructions. Load test battery at approximately one-half cold-cranking amperage rating for 15 seconds while observing battery voltage. If voltage reading is 9.5 volts or more, battery is okay. If voltage reading is less than 9.5 volts, charge battery and retest. If loaded battery voltage is still less than 9.5 volts after charging battery, replace battery.

NO LOAD TEST

Note. If no load voltage is to be measured with battery installed in vehicle, first disconnect ground strap. Vehicle must not be started or driven with tested battery for at least 2 hours before taking measurements. During this time, DO NOT allow load or additional charge to be applied to battery.

With battery installed and ignition switched off, check voltage between battery terminals with voltmeter. If no load voltage is 12.7 volts, or higher, battery is okay. If no load voltage is lower than 12.7, recharge battery, and repeat procedure. If battery voltage is still less than 12.7 after charging battery, replace battery.

REMOVAL & INSTALLATION

Air Bag

ECM

If connector is disconnected from ECM or battery is disconnected, all adaptation values in control module are erased. To achieve optimal anti-theft protection for vehicle, an anti-theft immobilizer was installed. Anti-theft immobilizer is a system for enabling/locking Engine Control Module (ECM) through the W-wire.

This system cannot be circumvented, it is necessary to perform adaptation of anti-theft immobilizer using VAS 5052 in On Board Diagnostic function. The great availability of equipment options makes adaptation of ECM necessary (e.g. cruise control system). This "writing" function is not possible with a generic scan tool, therefore it is necessary to use VAS 5052 in On Board Diagnostic function for this purpose. DTC memory content will remain intact however. If engine is started after this, a rough, uneven idle can result. In this case, ECM readiness code must be regenerated.

ECM Readiness Code

While limited diagnostic information is available, vehicle manufacturer does not support diagnostic information using aftermarket scan tools. To properly diagnose vehicle, it is recommended to use VAS 5051 scan tool with VAS 5051/1 adapter cable or VAG 1551 scan tool with 1551/3A adapter cable and VAG 1598/31 test box.

Readiness code must be generated when Engine Control Module (ECM) memory is cleared, battery voltage is disconnected or ECM is disconnected. To generate readiness code, vehicle must be stationary, transmission in Park or Neutral, all electrical consumers off, A/C switched off and coolant temperature at least 176° F (80° C). If possible, it is best to warm-up vehicle by test driving. Connect scan tool to DLC. DLC is located behind cover under left side of steering column.

Power Windows

After connecting battery, completely open and close all power windows.

Radio & Clock

Vehicles are equipped with an anti-theft stereo system that requires a code to activate. Record stereo code BEFORE disconnecting negative battery cable. Disconnect negative battery cable. Turn ignition to ON position. Reconnect negative battery cable. Enter code into stereo and reset clock.

Telematics

Note. A4 and A4 Quattro are equipped with Audi Telematics by OnStar(R).

To avoid unnecessary discharge of emergency (back-up) battery, it must always be switched off, prior to disconnecting vehicle battery, and switched back on after vehicle battery is reconnected.

Use VAS 5051 in mode "Guided Fault Finding". Enter appropriate model, equipment and model year. Press ">" to confirm. After control modules have been registered, and DTC memories checked, press "Go To". Use the following prompts to switch off/on emergency (back-up) battery

1. Select "Function/Component Selection".
2. Select "Body".
3. Select "Electrical Equipment".
4. Select "01 - On-Board Diagnostic Systems".
5. Select "Telematic".
6. Select "J526 - Telephone/Telematic Ctrl. Module, Service Mode Disc. Battery". If necessary, press ">" to advance.
7. To switch OFF emergency (back-up) battery, select/press button "3" - Service Mode Activating (No Load On Emergency Battery).
8. Follow tester prompts.
9. To switch ON emergency (back-up) battery, select/press button "1" - Service Mode Deactivating (Normal Operating Condition).
10. Follow tester prompts.

Note. Servicing of cooling system can be made easier by removing front bumper and moving lock carrier assembly away from engine. For bumper removal and lock carrier procedures, see appropriate procedure in REMOVAL & INSTALLATION article in ENGINE PERFORMANCE.

Removal & Installation (1.8L - AMB)

1. Turn ignition to OFF position. Disconnect battery ground strap.
2. Open cap on coolant expansion tank. Remove engine cover. On vehicles equipped with auxiliary heater, remove exhaust pipe and auxiliary heater bolts (arrows) at noise insulation panel. (Scheme 3)
3. On all vehicles, loosen screws or quick release (1 and 2), and remove front noise insulation panel. (Scheme 4) Place appropriate drip tray below engine. Pull off retaining clip (1), and remove engine coolant temperature sensor (2). (Scheme 5)
4. Drain coolant from radiator only. Disconnect upper coolant hose retaining bolts from coolant pipe (arrow). (Scheme 6) Remove radiator fan control module (arrow), and place aside. (Scheme 7)
5. To loosen serpentine belt, turn belt tensioner in direction of arrow. (Scheme 8) Remove belt from generator belt pulley. Release tensioner.
6. Remove upper and lower mounting bolts (arrows), and swing generator forward. (Scheme 9) Disconnect electrical harness connector (2). (Scheme 10) Remove terminal D+ (1) nut. Remove generator.
7. To install, reverse removal procedures. Ensure serpentine belt is correctly routed and properly seated. Tighten generator bolts and terminal connections to specification. See «TORQUE SPECIFICATIONS»(/audi/a4/b6-2000-2006/remont/charging-system/#generators-regulators__torque-specifications). Start engine, and check running of belt.

Scheme 3

Scheme 4

Scheme 5

Scheme 6

Scheme 7

Scheme 8

Scheme 9

Scheme 10

Removal & Installation (3.0L - AVK)

1. Pull front engine cover in direction of arrows, and remove. (Scheme 11)
2. Using chalk or felt pen, mark rotation direction of serpentine belt. To loosen belt, turn belt tensioner in direction of arrow. (Scheme 12) Remove belt from power steering pump pulley.
3. On vehicles equipped with auxiliary heater, remove exhaust pipe and auxiliary heater bolts (arrows) at noise insulation panel. (Scheme 3)
4. On all vehicles, loosen screws or quick release (1 and 2), and remove front noise insulation panel. (Scheme 4) Cut through cable ties (arrows). (Scheme 13) Open retainer for starter cable, and remove cable.
5. On vehicles equipped with automatic transmission, unscrew buts (1 and 2), and remove bracket for ATF lines. (Scheme 14)
6. On all vehicles, remove wiring from generator. Remove generator mounting bolts. (Scheme 15) Remove generator.
7. To install, reverse removal procedures. Ensure serpentine belt is correctly routed and properly seated. Tighten generator bolts and terminal connections to specification. See «TORQUE SPECIFICATIONS»(/audi/a4/b6-2000-2006/remont/charging-system/#generators-regulators__torque-specifications). Start engine, and check running of belt.

Scheme 11

Scheme 12

Scheme 13

Scheme 14

Scheme 15

Removal & Installation (4.2L - BHF)

Note. Manufacturer does not provide removal and installation procedures.

OVERHAUL

Note. Manufacturer recommends replacing generator as an assembly. Overhaul procedures are not available.

TORQUE SPECIFICATIONS

TORQUE SPECIFICATIONS

WIRING DIAGRAMS

Note. See CHARGING SYSTEM in appropriate SYSTEM WIRING DIAGRAMS article in ELECTRICAL.

See also:
• LOAD TEST
• WIRING DIAGRAMS
• TORQUE SPECIFICATIONS