A note from Bambu Lab website…
We’ve recently received a few feedback concerning unstable temperature readings and heating issues of our A1 printers. We’ve conducted a comprehensive investigation and believe that we need to take action to ensure the reliability and safety of our products.
The investigation has revealed that the cause of these issues is linked to the damage at the root of the cable which is the connecting point of the heat bed cable and the base of the printer. To a very small portion of A1 printers, excessive bending caused by external force leads to damage to the cable at the root. This damage might not immediately cause the cable to fail, but it will make the cable more susceptible to fatigue and damage in later use. Although the fuse on the heat bed will prevent the bed from overheating, and the fuse on the power supply will prevent any short circuits from developing into any meltdown, this damage will affect the reading of the temperature and may cause power loss or even short circuits. We think it is a serious threat to the safety that we should address.
Read more: A1 Heatbed Cable Callback