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Details
| Specification | Value |
|---|---|
| Brand | TOPRAN |
| Manufacturer Restriction | Bosch |
| Rated Voltage [V] | 14.6 V |
OE/OEM numbers (1)
Search by this OE number to find compatible parts
- AUDI / SEAT / SKODA / VW—028 903 803D
Where this part fits
Original-fit position for OE 028903803D. The red ring marks where this part installs on the vehicle.
About this product
The TOPRAN Alternator Regulator (100 343) 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: Manufacturer Restriction: Bosch, Rated Voltage [V]: Nylon, Plastic V. Each dimension is checked against the OEM reference to ensure the component seats and functions correctly first time. Verified to fit AUDI, SEAT, 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, 022018111LGK, 028 903 803D and 49 more. Matching these numbers confirms a like-for-like replacement with no loss of function. TOPRAN 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 from our UK warehouse with a 30-day money-back guarantee and free hassle-free returns.
About TOPRAN
TOPRAN, part of the Hans Thomsen Group headquartered in Hamburg, Germany, is a growing independent aftermarket brand focused on providing quality parts at accessible prices. TOPRAN offers a comprehensive range covering engine, cooling, electrical, braking, and body components for European vehicles. All TOPRAN products are manufactured to meet OE specifications and undergo quality testing before distribution. Combining German quality management with competitive pricing, TOPRAN is an excellent choice for cost-conscious motorists and workshops who do not want to compromise on part quality.
Suitable cars
Equivalent products (55)
Show all 55 OE numbers
Alternator Regulator TOPRAN 100 343 — compatible car models
| Car models | AUDI: 100 C4 Avant (4A5), 100 C4 Saloon (4A2), 80 B4 Avant (8C5), 80 B4 Saloon (8C2), A3 (8L1), A4 B5 (8D2), A4 B5 Avant (8D5), A6 C4 (4A2), A6 C4 Avant (4A5), A6 C5 (4B2, 4B4) (+2 more); SEAT: ALHAMBRA (7V8, 7V9), AROSA (6H1), CORDOBA (6K1, 6K2), IBIZA II (6K1), INCA (6K9), TOLEDO I (1L2); SKODA: FELICIA I (6U1), FELICIA II Estate (6U5), FELICIA I Pickup (6UF, 6U7), OCTAVIA I (1U2), OCTAVIA I Combi (1U5); VW: CADDY II MPV (9K9B), GOLF III (1H1), GOLF III Variant (1H5), GOLF IV (1J1), LT 28-35 II Bus (2DB, 2DE, 2DK), LT 28-46 II Platform/Chassis (2DC, 2DF, 2DG, 2DL, 2DM), LT 28-46 II Van (2DA, 2DD, 2DH) |
|---|---|
| Engines | 2.0 E; 2.0; 1.6 E; 1.6; 1.8; 2.8; 1.8 T 20V; 1.0; 1.0 i; 1.4 i; 1.6 i; 1.4; 1.4 16V; 2.5 SDI |
| Year of manufacture | 1989-2010 |
| Manufacturer article number (MPN) | 100 343 |
| OE part numbers | 028 903 803D |
Compatibility check
Loading vehicle data…
Please wait while we load vehicle compatibility information.Description and what's included
TOPRAN 100343 . Manufacturer Restriction: Bosch. Rated Voltage [V]: 14,6 V
- 1x Alternator Regulator
Shipping, returns, warranty
Free UK delivery on orders over £99.00. Express and standard shipping available.
- Standard delivery: 2-5 business days
- Express delivery: 1-2 business days
- 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 AUDI, SEAT, 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 TOPRAN Alternator Regulator have?
This TOPRAN Alternator Regulator has the following specifications: Manufacturer Restriction: Bosch; Rated Voltage [V]: 14,6 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: 028 903 803D. Cross-reference these numbers with your vehicle's original part number to confirm compatibility.
How much does a Alternator Regulator cost?
This TOPRAN Alternator Regulator is available for £13.99. Alternator Regulator prices vary depending on brand, specifications, and vehicle compatibility. TOPRAN 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 028 903 803D?
Yes, this TOPRAN Alternator Regulator is a direct replacement for OE part number 028 903 803D. 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.
