When your remote control stops working, it is best to quickly rule out the most common problem so you can focus on more challenging fixes.

Check the batteries. Weak batteries can cause erratic behavior or even prevent the remote from working at all. If you have a multimeter, check the voltage of each battery to make sure they are fresh.

If you don't have a multimeter, or if the multimeter shows that the batteries are no longer producing their rated voltage, pop in some new batteries and test to see if this cures the problem.