ERROR 25

[Tony]

fin_rad, the cost shown on the invoice was about £150 I think but mine was under warranty so not payable.

[atknow@gmail.com]

I have same situation. Only fix I've found is to unplug rear brake light.

[CrowNinja]

Howdy Folks.

Just signed up so I can reply to this.  New RadRover--well, one month old and ~100 miles on her.  I just installed the rear rack a few weeks ago.  I have seen this "Error 25" a few times now, but it is always the same:  I turn on the battery, press the Mode switch for the display, Error 25 flashes on the screen for a few seconds, then it goes away.  If I press the Mode button again, it is fine from then on. 
This is the *only* time I have seen the message.  And it has only happened about 3x now.  It has never stayed on. 
So reading through this thread, it seems it does have something to do with the cable extension from the controller through the cable that comes with the rear rack to the now relocated tail light.  At least in my case. 
It is nerve wracking to see that...because I then worry about something like, what if this came on and stayed on out in the boondocks somewhere?  But hopefully, that never happens.  And this thread has given me some things to try if it ever does.

Ride on! 

[Dnewhall]

I've had this issue for more than a month. Unplugging the tail light works, but swapping the tail light from my wife's Radcity doesn't help. This first occurred at about the one year mark. Waiting on Rad to see what to do next.

[wheelsurf]

I have  Rad City bike, hardly ever runs, yes error 25 comes up, but why doesn't Rad do something major to make this issue go away. I cannot use the bike because it always stops working and peddling a heavy e bike up hill at 70 years old is not something I cherish. I doubt I have 1 hour on it, so far, the bike is useless.

[DCH3416]

I have  Rad City bike, hardly ever runs, yes error 25 comes up, but why doesn't Rad do something major to make this issue go away. I cannot use the bike because it always stops working and peddling a heavy e bike up hill at 70 years old is not something I cherish. I doubt I have 1 hour on it, so far, the bike is useless.

So error 25 can represent a couple of conditions related to brake sensing. The easiest to trip is just having the brake lever active on startup. If one of the circuits are closed it'll trip the error, and releasing the brake is usually enough to clear it. Other conditions are related to electrical faults, whether that be related to perhaps activating the brake light or maybe a short somewhere in the wiring or circuitry. It's a difficult thing to diagnose, even presumably for Rad, when it seems to be sporadic and largely based on anecdotal evidence.

The best thing to do is attempt to narrow down which components are faulty. For example unplugging the taillight cable at the controller. Testing each of the components listed in the troubleshooting guide: https://radpowerbikes.zendesk.com/hc/en-us/articles/360010543453-Error-25-Troubleshooting-Guide

If we knew which models specifically are observing issues and roughly when they were purchased as well. Maybe there's a pattern there.

And yeah, some of it does rely on Rad. For example they have the source programming and schematics to see specifically what conditions are met to trip this error.

[DCH3416]

I wonder though, if this is an electronic problem with some controllers. Maybe there's a relay in there that handles disconnecting the motor when the brakes are applied.

[nutmeag]

Only 50 miles on my 2 week old Radwagon and getting the error.  Figured out it's the right break sensor because when I unplug on that side the error goes away (but comes right back as soon as I plug it back in). 

How do I actually solve the issue or do I need to contact Rad for a replacement part? 

[Veggyhed]

Same thing happens on my mini 4 2020. I do have a real light extension for my rack. I first noticed it when zip tie was too tight. So the cable now hangs loosely through several zip ties. If the cable is looped around itself it also sets off error 25. And only clear this error by turning the bike off turning the battery off with the key. Turn the battery on and then turn the bike on. What I noticed is if you turn the bike off when you have an error 25 the rear light seems to stay on. That's why I started turning off the battery with the key.

Sent from my Pixel 3a using Tapatalk

[mushroom]

I've just bought a secondhand radmini4
The seller said it had issues with the lights not working
I've got it home and fully charged the battery and it comes up with error 25
I've disconnected the cable to the back light and it works fine and no error code.
Is it just a case of replacing the back light ? 

[mushroom]

OK tried the back light from my wife's radrunner + and it's the same
Disconnected all the cables and plugged the back light into the stubby lead from the controller and still getting Error 25
There's no warranty so I'm just going to go for the 35amp controller from Big Game Bikes

[JedidiahStolzfus]

I put the 35A controller on my RR.  I didn't get it from where you're saying, but it's probably the same thing.  Install was easy enough.  I did have to drill one hole through the skidplate to mount the controller.  The rear hole lined up with the existing one. 

Toughest part was getting the wires routed.  The motor connector didn't want to slip by the fender.  Had to gently pry the fender away from the frame to get it to pass. 

There's also a rubber grommet where the cables come down from the front.  You'll have to pry that out without scratching the paint and then get it back in.  There's a connector inside the frame you'll need to get to for the new controller.

[mushroom]

I put the 35A controller on my RR.  I didn't get it from where you're saying, but it's probably the same thing.  Install was easy enough.  I did have to drill one hole through the skidplate to mount the controller.  The rear hole lined up with the existing one. 

Toughest part was getting the wires routed.  The motor connector didn't want to slip by the fender.  Had to gently pry the fender away from the frame to get it to pass. 

There's also a rubber grommet where the cables come down from the front.  You'll have to pry that out without scratching the paint and then get it back in.  There's a connector inside the frame you'll need to get to for the new controller.

mines on back order from https://biggamebikes.com/product-category/rad-power-bikes-upgrades. I shouldnt have the same problem as you with the wires, they don't pass through the frame on the radmini 4