A solid red light on a dock with a bike means that the bike is broken and cannot be used again until it’s been fixed by a CoGo technician. Sometimes friendly riders will turn the seat of a broken bike backward, so it’s easy to spot from afar and you don’t waste your time walking up to it. A red light on a dock without a bike means that there is a problem with the dock and it cannot accept bike returns.
If you ever take out a bike that has an issue, please return it to the closest dock and hit the button on the dock with the wrench symbol.
You can also get a red light when trying to release or return a bike - that generally means there's a problem, like an error entering the ride code or failure to dock a bike properly. If you get a ride light in response to an attempted action, please try again. A green light means you're ready to go.