Display comes on as normal then I get a Error 30 , communication error , I checked all the connections , they are good , any one else have this problem?
Error 30 represents the display having a hard time communicating with the controller module, and/or the other way around. May be from corrosion, noise in the line, cable damage, etc.
Unplug and plugging all of the cables between the display and controller (including the hard to reach 8 pin one underneath the crank), visually inspecting inside connectors for debris, perhaps adding a little dielectric grease for good measure.
I am having this problem with my Radwagon 4 which is almost 3 years old. About 2 months after the warranty expired, the main battery suddenly (without any warning or symptoms) died completely. After troubleshooting with Rad, I had to buy a new battery. Since receiving the new battery, I have had electrical issues. First, the front light died. It has now been replaced with a genuine Rad front light. Then, error 30 messages started. Now, they are persistent and I cannot use the bike with the motor. I have done the troubleshooting, checked the connectors. I think Rad sent a battery with faulty internal or external connectors. The new battery is still under warranty (about 6 months old), so I will contact Rad about a replacement, but I am super disappointed that I am having such frequent problems so soon after warranty expiration.