Controller light is always off
Checking method: use multimeter to measure whether there is voltage between controller B+ B - cables
A. If no voltage, then main circuit is open or power switch is damaged, this can be easily repaired.
B. If there is voltage, then controller is faulty and it needs to be replaced.
Required information for warranty claims:1. Photo of truck name plate;2. Video of controller appearance3. Video of voltage detecting between controller B+ B-cables and controller light being off.