Guide to the 2015-2020 Audi A3 Serpentine Belt
Understand the signs of a failing serpentine belt and how to choose the right replacement for your Audi A3.
- A squealing noise is the most common sign of a worn serpentine belt; inspect for cracks and fraying.
- If the belt breaks, the car is not drivable as the engine will overheat and the battery will not charge.
- INA and Gates are considered top-tier, OEM-quality brands for this application.
- It is strongly recommended to replace the belt tensioner at the same time as the belt.
Signs of a Failing Serpentine Belt
A serpentine belt is a wear item, meaning it will eventually need to be replaced. Ignoring the warning signs can leave you stranded. Be alert for these symptoms:
- Squealing or Chirping Noises: This is the most common sign. A high-pitched squeal, especially on startup or when the A/C is turned on, often points to a worn or loose belt. 🎬 Learn how to diagnose a noisy alternator pulley vs belt.
- Visible Wear: Inspect the belt. If you see cracks, fraying, missing chunks, or a glazed, shiny appearance on the ribbed side, it's time for a replacement.
- Accessory Failure: If your power steering becomes heavy, your A/C stops blowing cold, or the battery light illuminates on your dashboard, the belt may have slipped or broken completely.
- Engine Overheating: A broken serpentine belt will stop turning the water pump, causing the engine to overheat rapidly. If you see the temperature gauge spike, pull over immediately to prevent catastrophic engine damage.
A Note on Water Pump Issues
The 2015-2020 Audi A3, particularly models with the 1.8T and 2.0T engines, can be prone to premature water pump failure. Often, a whining noise or a coolant leak is mistaken for a simple belt issue when it's actually the water pump failing. Since the serpentine belt must be removed to replace the water pump, it is highly recommended to replace the belt and tensioner at the same time you service the water pump.
Choosing the Right Aftermarket Serpentine Belt
When replacing the serpentine belt, you have several quality aftermarket options. The key is to choose a brand known for its reliability in European applications.
- INA: INA is widely regarded as an Original Equipment Manufacturer (OEM) for many German automakers, including Audi. Choosing an INA belt or belt kit (which often includes the tensioner) is as close to factory quality as you can get. They are a top-tier choice for this vehicle.
- Gates: Gates is another top-tier brand and a major OEM supplier for many car manufacturers. Their belts, like the Micro-V line, are known for durability and quiet operation. You can't go wrong with a Gates belt on your A3.
- Dayco: Dayco is a well-established brand that produces reliable aftermarket belts. While some forum users have expressed preferences for INA or Gates tensioners, Dayco belts themselves are considered a solid, standard-quality replacement part.
Pro Tip: Always replace the belt tensioner along with the serpentine belt. The tensioner is a spring-loaded pulley that keeps the belt tight. It experiences the same wear and tear as the belt, and a failed tensioner can cause a new belt to slip or fail prematurely.
Cost of Replacing Your Serpentine Belt
The cost is relatively low for the part itself, with labor being the larger portion of the expense if you use a repair shop.
| Part or Service | Estimated Cost |
|---|---|
| New Aftermarket Serpentine Belt | $17.76 - $40.30 |
| Shop Labor | $100 - $180 |
| Total Professional Replacement | $120 - $220 |
Frequently Asked Questions
When should I replace my Audi A3's serpentine belt?
There is no universally fixed interval, but a general guideline is to inspect it during routine oil changes and plan for replacement every 60,000 to 90,000 miles, or sooner if you notice any signs of wear like cracking or squealing.
Is replacing the serpentine belt a DIY job?
Yes, for a mechanically inclined person. The job involves relieving tension on the belt tensioner (usually with a 16mm wrench), slipping the old belt off, and routing the new one correctly. It is crucial to have the correct belt routing diagram, which is often on a sticker in the engine bay. 🎬 See professional tips for routing and installing your new belt. The difficulty is low, but access can be tight.
🎬 Watch this step-by-step 2.0 TSI serpentine belt replacement guide.Are there any recalls for the serpentine belt on the 2015-2020 A3?
No. Searches of the National Highway Traffic Safety Administration (NHTSA) database show no recalls specifically for the serpentine belt on the 2015-2020 Audi A3. There have been other recalls for this vehicle, but none related to the belt drive system.
Should I buy a belt kit or just the belt?
It is highly recommended to buy a kit that includes the serpentine belt and the tensioner. The tensioner wears out at a similar rate to the belt. Replacing only the belt can lead to premature failure if the old tensioner is weak or fails.
Helpful Videos
Technical Specifications
OEM Part Numbers: 06K903137T 06K903137G
The most common belt for the 2.0T engine is a 6-rib belt with a length around 1005mm (e.g., 6PK1005). However, different engine codes and accessory configurations may use slightly different lengths. Always verify the correct part number for your specific vehicle VIN.
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The information in this article is provided for general reference and educational purposes only. Vehicle specifications, procedures, and part compatibility can vary by production date, trim level, and region. Always consult your vehicle's factory service manual and verify part numbers before purchasing or performing repairs. Safety-critical components such as airbags, seat belts, and braking systems should be installed by a qualified professional.
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