Display shows E8 and the mower stops; may be accompanied by unusual noises from the drive system.
Safety Warning
This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.
If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.
Possible Causes
How to Fix / Troubleshooting
Safety first: Switch the mower OFF and remove it from wet areas before inspection.
- Check for moisture: Inspect the underside and wheel housings for signs of water ingress or mud. Allow the mower to dry in a sheltered, ventilated area for at least 24 hours if it has been exposed to heavy rain or sprinklers.
- Visual cable inspection: Look for damaged or pulled cables leading to the drive motors. Do not pull on the cables; just inspect for cuts or crushed sections.
- Compare wheel behavior: On a flat surface, gently push the mower forward and backward with power OFF. Listen for abnormal grinding or scraping from either drive motor.
Because E8 typically indicates an electrical fault, further diagnosis requires resistance and insulation testing of the drive motors and motor driver circuits, which should be performed by a Stihl service technician. Replace the affected drive motor or main PCB as recommended.