Our 3 year-old Radwagon 4 suddenly decided not to start this week, just before back-to-school when we really need it.
All connectors are fine. I have checked the battery and connections with a multimeter. The fully charged battery is delivering 54V and the controller is sending 54V to the screen (bottom 2 pins on the 5-pin connector).
Is this enough to confirm that the controller is OK, but the screen is dead?
I have the same issue on my Rad Rover 3 years old. Was out riding and suddenly went dead. Battery was in full bars just prior . Display is blank; lights don't work . Throttle is dead . Test voltage on battery and got 54 volts . Test voltage on output cable of battery tray and got 54 volts . Intersestingly and unexplained is I get 40 volts at same location ( base of battery two outer pins) with key turned off ???
Contacted RAD . They sold me a new controller. Put that in . no change. I have disconnected and reconnected all harness commections . No visible damage. Bike always stored inside . Never gotten really wet ( slight rain conditions occasionally )
It could be the issue I had. I used the throttle often and I overheated the battery connector (cradle side) and it melted and expanded. I replaced the cradle battery terminal due to melting issues.
Probably the fastest way to tell is if the battery is difficult to remove from the cradle. The plastic expands making it difficult to remove. The sure way is to open the cradle side to see any signs of melting.
Replacing the connectors (I replaced both sides one on battery and one on cradle) was not difficult. I think I just did wire crimping. I replaced battery side because the replacement was not an exact fit.
Purchased from Amazon for about $12.