A robot mower that will not charge or return to its base is usually blocked by dirty or corroded charging contacts, no power reaching the dock, a docking station placed where the mower cannot line up with it, or a boundary and guide signal the mower can no longer follow home.
The usual causes
- Dirty or corroded charging contacts. The metal strips on the mower and the dock build up oxidation, grass film, and moisture residue. Poor contact means the mower parks but never draws a charge.
- No power at the dock. A tripped outlet, a cut or chewed low-voltage cable, or an unplugged power supply leaves the base dead even though the mower docks correctly.
- Docking station placement. A dock on a slope, on uneven ground, or too close to a wall or corner can stop the mower from aligning its contacts.
- Lost return path. Boundary-wire mowers follow the perimeter wire or a guide wire back to the dock; wire-free RTK mowers navigate by satellite position. A break, a signal drop, or a poor return location blocks the trip home.
- Depleted or aging battery. A battery near the end of its service life may report a charge it cannot hold, so the mower leaves the dock and stalls quickly.
Fixes to try in order
- Clean both sets of contacts. Power down the mower, then wipe the charging strips on the mower and the dock with a dry cloth or fine abrasive pad until the metal is bright. Remove any grass or debris packed around them.
- Confirm the dock has power. Check the outlet with another device, inspect the full length of the low-voltage cable for cuts or rodent damage, and verify the power supply indicator light if the model has one.
- Reseat the mower by hand. Place it on the dock manually and watch whether the charge indicator responds. If it charges when placed by hand but not on its own, the problem is the return path or alignment, not the charger.
- Check the docking approach. Make sure the dock sits on firm, level ground with clear space in front of it. Clear grass clippings, sticks, and standing water from the approach lane.
- Test the boundary and guide signal. For wire-based systems, confirm the base station signal light is steady and walk the perimeter for visible wire breaks. For RTK systems, confirm the reference antenna has a clear sky view and a stable satellite fix before the return trip.
When it is the mower, not the lawn
If the contacts are clean, the dock has power, and the mower still will not charge or find its way home, the fault may be internal. A battery that drops charge within minutes, a charging circuit that never engages a clean hand-placed dock, a failing position sensor that misreads the approach, or a firmware regression that changed docking behavior after an update can each produce these symptoms. Note whether the trouble began right after a firmware update, since that points to software rather than hardware. Watch for known model issues and update notes on the Tracker, and see our overview of robot mower autonomy.