Replacing the battery in your 2016 Audi A3 might seem straightforward, but modern vehicles like the A3 require a bit more attention than just swapping out parts. This article will guide you through understanding the essentials of battery replacement for your 2016 Audi A3, focusing on clearing diagnostic trouble codes (DTCs) and the importance of proper battery coding.
If you’ve already performed a scan with VCDS (VAG-COM Diagnostic System), you’re one step ahead. To quickly clear any DTCs that might be lingering after a battery change or other maintenance, VCDS offers a convenient shortcut. Navigate to [Options] then [Gateway Installation List] and select [Clear All DTCs]. This command sends a system-wide request to clear diagnostic codes across all modules in your Audi A3. After running this, ideally, more modules should report back in black, indicating no faults, rather than red.
Now, let’s talk batteries. When it comes to battery replacement in a sophisticated vehicle like the Audi A3, opting for the correct, dealer-recommended battery and ensuring it’s properly coded is generally the best practice. Battery coding is crucial, and resources like the Ross-Tech Wiki on Battery Replacement provide valuable information. For your 2016 Audi A3, which uses the 19-CAN Gateway with UDS/ODX, correct coding is essential for optimal battery life and system performance.
While a correctly installed and coded battery from the dealer can often last for eight years or more, aftermarket batteries might present variable results. You might get lucky with four years of service, or you might encounter issues much sooner, perhaps even within nine months. The potential problem with aftermarket batteries arises because the vehicle’s energy management system is designed to charge and maintain a battery based on specific parameters. If these parameters are not correctly programmed for the aftermarket battery, the system might overcharge or undercharge it, leading to reduced lifespan. Even a small discrepancy in charging parameters, say 4%, might eventually cause problems, while a larger mismatch, like 20%, could significantly shorten the battery’s life.
You mentioned installing an AAA battery (Group 48-C) with a 120Ah rating, replacing the original Varta 72Ah battery. It’s important to note this significant difference in Amp-hour (Ah) capacity. While a higher Ah rating isn’t inherently bad, the car’s energy management system needs to be aware of this change to manage charging correctly. Ideally, when coding the new battery, you would input the correct Ah rating.
It appears AAA sources batteries from manufacturers like East Penn, possibly under the DEKA brand. These batteries might not come with a Battery Energy Management (BEM) code, which simplifies the coding process.
If you cannot find a BEM code for your AAA battery, you might need to manually input the battery parameters into VCDS. Some users have reported success by slightly altering the serial number of the old battery in the coding to register the new battery. However, for optimal performance and longevity, especially with the increased Ah rating, it would be best to adjust the battery capacity and ideally other parameters if known, during the coding process using VCDS. Consult the Ross-Tech Wiki and VCDS documentation for detailed steps on battery coding and adaptation for your 2016 Audi A3.
