When the temperature drops, the car's system becomes particularly sluggish. The loudspeaker on the driver's side is very loud while the others are silent, and the radar gives false alarms and keeps beeping. Has anyone else encountered similar issues with their car? How did you solve them?

Whenever I used to brake, my Land Cruiser would occasionally emit a beeping sound, similar to the reverse radar sound. Recently, it happens every time I brake. Does anyone know what the issue might be?

Jetur X70, 2020 model. I started having a coolant leak, and when pressure was applied, the leak point was found. The four-way valve was replaced, and the heating pipe and water inlet pipe were tightened. It was also discovered that the water pump was leaking, and eventually, everything was replaced. However, after refilling the coolant, the mechanic found that the engine temperature was high, but it drops as soon as the heater is turned on. They spent half a day but couldn't find the problem, and the car not being fixed has caused a lot of issues. Have you encountered this before? How did you handle it?