What Causes the Malfunction Light to Illuminate After Replacing a Car Battery?

[McAdalynn]

The reason the malfunction light illuminates after replacing a car battery is that disconnecting the battery to replace it clears the driving data stored in the vehicle's computer, including system correction data such as throttle opening and fuel injector spray volume. The specific reasons and solutions are as follows: Driving Data Cleared: After replacing the battery, previously stored data such as throttle opening and fuel injector spray volume are reset to factory settings. However, since carbon deposits may have accumulated in components like the throttle body, fuel injectors, and combustion chamber, deviations from the factory settings can lead to issues such as improper air-fuel mixture. Solution: Continue driving for a while, and the vehicle's computer will gradually recalibrate and compensate for these data, restoring them to pre-replacement levels. At this point, the malfunction light should turn off. If the issue persists for an extended period, it is advisable to visit a 4S shop for inspection.