What is the reason for the fault light coming on after replacing the battery in the Tiguan?
2 Answers
The reason for the fault light coming on after replacing the car battery is due to a malfunction in the battery's charging controller. If the battery's charging controller is faulty, it is necessary to promptly visit the car's 4S store or a repair shop to inspect or replace the battery charging controller to resolve the battery fault. Avoid long-term parking: Avoid parking the car in an open parking lot for extended periods. If long-term parking is unavoidable, the battery should be removed and taken away to prevent damage from freezing. Difficult engine starting: Car engines are harder to start in winter. Each attempt to start the engine should not exceed 5 seconds, with a minimum interval of 15 seconds between attempts. If the engine does not start after several attempts, check other aspects such as the electrical circuit, ignition coil, or fuel system. Avoid continuous attempts to start the engine, as this can lead to battery damage due to excessive discharge. Regular charging: Car batteries need to be charged regularly. A battery left unused for a long time will gradually discharge on its own until it becomes unusable. Therefore, the car should be started periodically to charge the battery.
I just replaced the battery in my Tiguan and the malfunction light came on. This has happened to me several times. The usual reason is that when the battery is replaced and the power is disconnected, the car's computer ECU automatically resets and enters self-check mode. At this time, the voltage is unstable, and false alarms are quite normal. It's like when a phone reboots and needs to load the system—the car also needs time to adapt to the new battery's current. Usually, driving a few dozen kilometers or taking it on the highway to let the system self-learn will make the light go off. If the light remains on, it might be because the battery terminals aren't tightened properly or there's poor contact in the wiring. You should check if the negative terminal is secure. Don’t worry too much about safety—it's just a warning signal. Next time you replace the battery, I recommend turning off the engine and disconnecting the power first, then waiting a few minutes before proceeding to avoid false triggers. If all else fails, spend a little money to have a professional shop scan the fault code for peace of mind.
