Bosch error 860: ABS power supply fault
The ABS unit is not receiving a stable supply voltage. The ABS warning lamp stays on and ABS is switched off, but the brakes work as normal brakes and the motor keeps assisting. It usually points to the ABS power cable or its connector rather than the battery.
Likely causes
- Loose or corroded ABS power connector
- Damaged ABS supply cable
- Battery contacts poor, causing voltage dips
- Faulty ABS unit
How to fix Bosch error 860
- Check the battery is seated and its contacts are clean
- Check the ABS unit's connectors and cable for damage or moisture
- Restart and test
- If the code returns, a dealer must measure the supply and test the harness with DiagnosticTool
Warranty: The ABS module is a Bosch component with the same 2-year warranty as the rest of the system; damaged sensor cables or bent sensor brackets from crashes are not covered.
Typical cost: A cable or connector repair 30-80 EUR/USD plus labour; an ABS unit 400-700 EUR/USD.
Frequently asked
Can I reset Bosch error 860 myself?
Only by fixing the connection and restarting.
Can I keep riding with error 860?
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 860 covered by warranty?
The ABS module is a Bosch component with the same 2-year warranty as the rest of the system; damaged sensor cables or bent sensor brackets from crashes are not covered.
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.