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Error 21 + Area13 Compatibility?

Started by birding-on-battery, April 16, 2023, 03:39:26 PM

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Hi all,

I have a rad city 5 plus step-thru that I purchased last April. Naturally just after my warranty is up... I get an error 21 issue. Thought it was the cracked top battery mount, but after replacing that today I still have error 21.

I think it's a controller issue, and I think it's most likely a cable failing because the controller is so crammed into the space in the bottom of the bike's frame.

So my question would be, since the bike is out of warranty now anyway, is the Area13 upgrade kit working on anyone's radcity? The product page says it's not officially tested by them on it. Do I go with area13 or buy yet another rad controller? Maybe I'll ask for two so I can replace it in another 8 months lol


Did you end up installing the upgrade controller? I'm working on installing one of these on my 5+ step thru and I am finding that a lot of the cable connectors do not match up.


Also looking for confirmation that this works with the RC5+ but I have the high step version.