Ten paces yesterday, an arm length today: a suddenly shortened range almost always has one of three causes, and two of them you fix yourself.
The clean range test
Insert fresh brand batteries and test outdoors with a direct view of the vehicle. Only under these conditions does the range say anything about the condition of the device, everything else really measures the surroundings.
Surroundings as a range killer
In halls, between containers or next to active radio systems every radio link shrinks. Therefore always compare with the open field before suspecting the device, often the pattern resolves itself that way.
Antenna and RF section
If the range stays short even in the clean test, the antenna is damaged or the RF section weakened, often after drops or moisture. That cannot be fixed from the outside, send the device in for a check.
Frequently asked questions
How much range is normal?
Outdoors the control reliably covers the usual working area around the vehicle. What matters is less the absolute value than a sudden deterioration.
The range fluctuates from day to day, what does that mean?
Fluctuations suggest batteries at their limit or changing interference. A constantly short range despite fresh cells suggests a fault.
Can I retrofit a stronger antenna?
No, radio systems are approved as a unit and must not be modified. The right way is repairing the existing antenna.