Bosch error 602: Internal battery error during charging
The battery has reported an internal fault while charging, or when the charger is connected on the bike. The BMS may stop the charge. It can be a one-off, but a repeating 602 usually means the battery or charger needs testing.
Likely causes
- Charger connected while the system was switched on, causing a handshake fault
- Faulty or non-Bosch charger
- Battery too cold or too hot to charge
- Dirty charging socket or charger plug
- Cell or BMS fault inside the battery
How to fix Bosch error 602
- Disconnect the charger and switch the system off
- Let the battery reach room temperature
- Check the charging socket and charger plug for dirt or damage
- Charge the battery off the bike with the original Bosch charger and watch the LED
- If the code returns or the charger stops early, a dealer must test the battery and charger with DiagnosticTool
Warranty: Bosch batteries carry a 2-year warranty (or 500 full charge cycles, whichever comes first); deep discharge from long storage is often classed as user damage.
Typical cost: A new Bosch charger is about 80-120 EUR/USD; a replacement battery 500-900 EUR/USD.
Frequently asked
Can I reset Bosch error 602 myself?
Disconnect the charger, restart and try charging again. If it repeats, the battery or charger must be tested; no user reset exists for the BMS.
Can I keep riding with error 602?
Usually, but with reduced or interrupted assistance and the risk of the system shutting down mid-ride. Ride home carefully or on muscle power alone; do not plan long rides until the cause is found.
Is error 602 covered by warranty?
Bosch batteries carry a 2-year warranty (or 500 full charge cycles, whichever comes first); deep discharge from long storage is often classed as user damage.
Related Bosch codes
Not an official Bosch document. Compiled from workshop experience and public service information; details can differ per system version and bike brand.