Is a battery charger sufficient for a remap?

We’ve all seen mobile remapping pictures on social media, with a car being mapped whilst attached to a cheap battery charger. Why is this not acceptable? Why do we invest in expensive battery conditioners rather than a simple charger from the motor factors?

The Electronic Control Unit (ECU) is the brain of a modern car, responsible for managing various functions such as fuel injection, ignition timing, and emissions control. For optimal performance, the ECU requires a stable and sufficient voltage supply, typically within the range of 9 to 14.5 volts. This minimum voltage is crucial for several reasons:

1. Data Accuracy and Processing: The ECU processes a vast amount of data from sensors throughout the vehicle. Accurate sensor data is vital for the ECU to make real-time decisions. A drop below the minimum voltage can lead to inaccurate sensor readings, resulting in poor engine performance and efficiency.
2. Memory Retention: ECUs have memory modules that store critical data, including fault codes and operational parameters. Adequate voltage is necessary to maintain this data, especially when the engine is off. Insufficient voltage can result in data loss, affecting the ECU’s ability to perform self-diagnosis and adaptive learning.
3. Component Protection: Modern ECUs are sophisticated and contain sensitive electronic components. A stable voltage helps protect these components from damage due to power fluctuations. Voltage drops can cause components to operate outside their safe parameters, leading to premature failure.
4. Communication with Other Systems: The ECU communicates with other onboard computers and modules via the vehicle’s communication network. A minimum voltage level ensures reliable communication and coordination between different systems, essential for integrated vehicle operations like stability control and anti-lock braking systems.
5. Software Integrity: ECUs run complex software that controls various vehicle functions. Consistent voltage levels are necessary to ensure the software runs correctly without glitches or crashes. Voltage dips can disrupt the software operation, potentially causing the ECU to enter a fail-safe mode or shut down entirely.
6. Reprogramming and Updates: ECUs often require reprogramming or software updates to improve performance or fix issues. These procedures demand a stable voltage supply, typically around 12.6 to 13.5 volts for modern ECUs1. Insufficient voltage during these processes can lead to incomplete programming or even corrupt the ECU software.

Our GYS battery conditioner can supply a stable voltage, set by us, up to and including a current draw of 120 amps! This ensures that all the systems and parameters stated above receive the voltage required to work as intended during the mapping process. A simple battery charger will deliver a current in the region of 2-5 amps, which is far short of what would be required, as seen in the picture, showing the current draw seen during a map on an Audi RS3 at Gotboost drawing 59 amps. We have even seen 100 amps being drawn by some vehicles when the coolant fans come on during the process!

In short, whenever you shop for a remapper, Ask if a battery support unit will be used, and ask what current (amp rating) it is. 

If they answer that they will use a battery charger/jump leads or that such a device isn’t necessary we urge you to walk away.