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Genuine VW/Audi Voltage Regulator | 077903803D

Audi A6 Quattro, Q7, A8 Quattro, S6, S8
VW Touareg, EuroVan
$237.99
Reg
$247.91
List
$233.33
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Make Sure It Fits

P/N: 077903803D Genuine VW/Audi FREE SHIPPING
Description:
Included with alternator.
VW: 3.6L, 190 amp, from 12/06. 3.0L, to vin 7la005000. For Alternator#021 903 025 T.
Audi: A8. 3.6L, 190 amp. Q7. S6. 4.2L.
Your part is located within diagram as #5.
Cross References:
  • 077903803B
  • VW077903803D

Voltage regulators maintain a constant range of alternator voltage output and convert the alternate current (AC) produced by the alternator into the direct current (DC) the vehicle operates on. As the alternator turns, it uses coil windings and magnets to create the alternate current. The faster the alternator turns, the more current and voltage is produced. The voltage regulator uses diodes to convert the AC to DC, limiting the alternator's voltage output to 12-14 volts.

Voltage regulators fail when they can no longer convert alternate current to direct current or when they can no longer maintain a consistent voltage that the vehicle requires to operate.

Signs of a faulty voltage regulator include:
  • Surging lights
  • Flickering interior lights
  • Instrument cluster or panel malfunctioning
  • Battery light or check engine light illuminated
  • A battery not being charged

Checking battery voltage or alternator output are simple ways to test a voltage regulator. Fluctuating battery voltage or drops in alternator output when the engine is at idle indicates the voltage regulator has failed and is not regulating voltage or not converting alternate current to direct current.

Replacing Your Vehicle's Voltage Regulator

Some voltage regulators are external to the alternator and can be removed and replaced in series with the alternator output circuit. Other voltage regulators are mounted inside of the alternator and may be removable and replaceable, but some will require the replacement of the alternator to replace the voltage regulator.

View more Genuine VW/Audi Voltage Regulators.

Any Genuine brand part is obtained directly through our vehicle dealership network from your vehicle's manufacturer. This is always your best option for getting the exact same part that is being replaced and will be the latest version design.
Left = Driver side and Right = Passenger side.
All parts are priced individually unless identified as a set or kit. "Per car" notes identify how many of a given part your car has and "Left/Right or Front/Rear" notes means the part fits the left or right side of the car. These parts are still sold individually and you'll need to select the appropriate quantity if you plan to replace more than one of this item.

Frequently Viewed Together

We found 2 additional part(s) that are frequently viewed together.

Why Buy OEM & Genuine Replacement Auto Parts from AutohausAZ?

Auto parts at wholesale prices is what you will find at AutohausAZ. Have you been searching the web for auto parts for your vehicle? You have come to the right place! Here at Autohaus, we strive to offer low prices on quality replacement parts and providing first rate customer service.

What This Genuine VW/Audi Voltage Regulator Fits?

Application information below is for reference only and should not be used to determine the exact vehicle fitment. Please use the "Make Sure It Fits" vehicle selection box above to determine the exact fitment and review any application notes. If you need any help determining if this part works with your vehicle, please don't hesitate to contact us.

Audi
05-08 - A6 Quattro
04-11 - A8 Quattro Base, L
07-09 - Q7 Base, Premium
07-10 - S6
07-09 - S8
VW
03-03 - EuroVan
07-10 - Touareg Base, TDI