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Details
| Specification | Value |
|---|---|
| Brand | AIC |
| Support plate diameter [mm] | 14 mm |
| Operating voltage [V] | 14.5 V |
OE numbers (7)
Search by this OE number to find compatible parts
- SKODA / VAG / VW—021 903 803B
- SKODA / VAG / VW—028 903 803B
- SKODA / VAG / VW—028 903 803C
- SKODA / VAG / VW—028 903 803D
- SKODA / VAG / VW—028 903 803G
- SKODA / VAG / VW—054 903 803
- HITACHI—130557
Where this part fits
Original-fit position for OE 028903803C. The red ring marks where this part installs on the vehicle.
About this product
The AIC Alternator Regulator (51423) is a professional-grade replacement component engineered for long service life and reliable operation across all conditions your vehicle encounters. The part is built to the following specification: Support plate diameter [mm]: Nylon mm, Operating voltage [V]: Nylon, Rubber V. Each dimension is checked against the OEM reference to ensure the component seats and functions correctly first time. Verified to fit SKODA, VW models. All compatibility data is cross-checked against the TecDoc database — select your vehicle to confirm the part matches your specific engine and year. This part supersedes original equipment references: 00127, 010.1632, 021 903 803B, 028 903 803B and 44 more. Matching these numbers confirms a like-for-like replacement with no loss of function. AIC is a recognised supplier of automotive replacement components to independent workshops and dealer networks across Europe. All parts are sourced from authorised distribution channels and carry full manufacturer traceability — you receive exactly the same component supplied to professional garages and dealer workshops. If fitment or specifications do not match your vehicle, our technical team can help identify the correct alternative — use the vehicle selector or contact us with your VIN for a guaranteed-fit recommendation. Replacing worn components on schedule preserves your vehicle's safety, reliability, and resale value — and aftermarket parts from established brands deliver OEM-equivalent performance at a fraction of the dealer price. Every part is dispatched with tracked delivery and a 14-day money-back guarantee with hassle-free returns.
Suitable cars
Equivalent products (43)
Show all 43 OE numbers
Alternator Regulator AIC 51423 — compatible car models
| Car models | SKODA: FELICIA I (6U1), FELICIA I Estate (6U5), FELICIA II (6U1), FELICIA II Estate (6U5), FELICIA I Pickup (6UF, 6U7), OCTAVIA I (1U2), OCTAVIA I Combi (1U5); VW: GOLF III (1H1), GOLF III Cabriolet (1E7), GOLF III Variant (1H5), GOLF IV Cabriolet (1E7), PASSAT B3/B4 (3A2, 35I), PASSAT B3/B4 Variant (3A5, 35I), POLO (6N2), POLO III (6N1), POLO III CLASSIC (6V2), POLO Variant (6V5) (+2 more) |
|---|---|
| Engines | 1.6; 1.4; 1.4 16V; 1.0; 100 1.4 16V; 100 1.6; 1.8 T 20V |
| Year of manufacture | 1988-2010 |
| Manufacturer article number (MPN) | 51423 |
| OE part numbers | 021 903 803B, 028 903 803B, 028 903 803C, 028 903 803D, 028 903 803G, 054 903 803, 130557 |
Compatibility check
Loading vehicle data…
Please wait while we load vehicle compatibility information.Description and what's included
AIC 51423 NEW MOBILITY PARTS. Operating voltage [V]: 14,5 V. Support plate diameter [mm]: 14 mm
- 1x Alternator Regulator
Shipping, returns, warranty
Free UK delivery on orders over £99.00. Tracked standard shipping.
- Standard delivery: 5–9 business days
- Order before 5pm — ships the next working day
- Free returns within 14 days
- All parts backed by manufacturer warranty
Warranty: 12-month manufacturer warranty on all parts. 14-day money-back guarantee if the part doesn't fit your vehicle.
Frequently Asked Questions
Is this Alternator Regulator compatible with my car?
This Alternator Regulator fits SKODA, VW vehicles. Use the vehicle selector at the top of the page to check exact compatibility — enter your car's make, model, and engine for a confirmed fitment match. All fitment data is verified through TecDoc.
What specifications does this AIC Alternator Regulator have?
This AIC Alternator Regulator has the following specifications: Support plate diameter [mm]: 14 mm; Operating voltage [V]: 14,5 V. Check the full specifications table above for complete details.
What OE part numbers does this Alternator Regulator replace?
This Alternator Regulator replaces OE part numbers: 021 903 803B, 028 903 803B, 028 903 803C, 028 903 803D, 028 903 803G, 054 903 803, 130557. Cross-reference these numbers with your vehicle's original part number to confirm compatibility.
How much does a Alternator Regulator cost?
This AIC Alternator Regulator is available for £17.99. Alternator Regulator prices vary depending on brand, specifications, and vehicle compatibility. AIC parts offer a balance of quality and value, backed by our 14-day money-back guarantee.
How do I know when to replace my Alternator Regulator?
Regular inspection of your Alternator Regulator is recommended as part of routine vehicle maintenance. Watch for changes in performance, unusual noises, or visual signs of wear. Consult your vehicle's owner manual for manufacturer-recommended replacement intervals specific to your make and model.
What tools do I need to replace a Alternator Regulator?
Tools required vary by vehicle make and model. Generally, a basic socket set, screwdrivers, and vehicle-specific tools may be needed. We recommend consulting a workshop manual for your specific vehicle, or having the Alternator Regulator fitted by a professional mechanic.
Can I use this part as a replacement for OE 021 903 803B?
Yes, this AIC Alternator Regulator is a direct replacement for OE part number 021 903 803B. It is manufactured to meet or exceed original equipment specifications, ensuring proper fitment and performance. All cross-reference data is verified through TecDoc.
Related categories
Common OE numbers for this part
Common original equipment numbers linked to stocked alternatives.
