Super73: charger light flashes red, or stays green and the battery won't fill

You plug in your Super73 and the charger light flashes red, or it stays green the whole time and the battery never fills. Super73's article on identifying a failed charger covers both (Super73 charger article). Short answer: a flashing red light is a charger failure sign, so stop using that charger. A light that stays green with the battery on, or a battery that won't reach 100%, doesn't prove the charger has failed, and needs more checks.

What the lights mean

From Super73 (Super73 charger article):

• Solid red: charging.
• Solid green: charging complete.
• Flashing red: a charger fault.

On the S1, OG, Z1, ZX and Z Miami, a charger left connected for a long time may switch from green back to red to top off the battery, then return to green. Super73 says this is normal. On the R, RX and S2, the battery shuts off automatically when charging is complete (same article).

Most likely cause

Super73 treats a flashing red light, a light that doesn't work at all, a hot charger, exposed wiring, sparking or a smoke smell as signs the charger itself has failed (Super73 charger article). A light that stays green while connected to the bike, different behavior on and off the bike, or a battery that won't reach 100% are signs to troubleshoot the bike to find the root cause (same article).

Other causes to rule out

• A battery left empty. Super73's handbook guidance, quoted in the article, is not to store the battery empty for more than 24 hours (Super73 charger article).
• A charger left on too long. The same guidance says not to leave the charger connected for more than 48 hours in a row, and to unplug it when not in use (same article).
• Loose or damaged connections between the battery and controller, part of Super73's initial checks (Super73 initial troubleshooting).

How to confirm

1. Plug the charger into the wall first and look at the light, then connect it to the bike and watch it again.
2. If it flashes red, or shows any failure sign above, stop and don't reconnect it (Super73 charger article).
3. If it stays green on the bike, check the charge port for dirt or bent contacts and try another outlet. See check your charger.
4. Note whether it behaves differently charging on the bike versus off the bike, which Super73 says points to the bike side (same article).
5. On an S1, OG, Z1, ZX or Z Miami, don't mistake the normal top-off switch from green to red for a fault.
6. If you're unsure, call Super73 support during business hours, as the article suggests.

Fix options

Replace the charger (easy)

If the charger shows a failure sign, replace it with the correct Super73 charger for your model. Super73's support hub links its replacement parts store and warranty pages (Super73 support).

Find the bike side fault (pro or Super73 support)

A charger that stays green or a battery that won't fill, when the charger tests fine, can point to the battery, the charge port or the wiring. Leave this to Super73 support or a service center. Don't try to open the battery.

Parts

• E-bike charger
• Battery charge port
• E-bike battery

When to get a pro

Get help if a new charger behaves the same way, if the battery gets warm while charging, or if range has dropped sharply. See battery won't charge, e-bike battery care and Super73 troubleshooting.

Sources

• Super73 charger article, support.super73.com
• Super73 initial troubleshooting, support.super73.com
• Super73 support, super73.com

Stuck after these checks? Find a shop near you.