Sadly SMC really can’t be told to ignore a sensor. Besides it’s best to fix the root issue. Time to inspect things if you have the skills otherwise it’s time to visit someone who has the skills. Someone who fixes Macs often. Apple no longer services this series sadly.
Let’s do this as the issue maybe an easy one! Often time the battery sensors are the issue. Install [https://www.coconut-flavour.com/coconutbattery/|CoconutBattery] with the charger plugged in take a screen snapshot of the main window posting it here for us to see.