A robot pool cleaner that will not turn on or charge is usually stopped by something in the power path: a tripped GFCI outlet, a loose or damaged power cable, dirty or corroded charging contacts, or a battery that has drained too far to wake, so check the supply and connections before assuming an internal fault.
The usual causes
- Tripped or faulty GFCI outlet. Most pool cleaners plug into a ground fault outlet that trips easily near water. If the unit is completely dead, rule this out first.
- Loose or damaged cable. A power supply cable that is cracked, kinked, or not fully seated can interrupt the connection without any visible sign.
- Dirty or corroded charging contacts. On cordless models, pool chemicals and mineral buildup can coat the metal contacts and block the charge from passing.
- Deeply drained battery. A cordless battery left flat for weeks can fall below the level the charger needs to begin, so it may appear dead even when the charger works.
- Power supply or brick fault. The external transformer or power brick can fail while the cleaner itself is fine.
Steps to try
- Reset the outlet. Press the reset button on the GFCI, or try a different known-good outlet. Confirm the outlet has power with another device.
- Inspect the full cable run. Check both ends are firmly seated and look along the whole length for cuts, crush marks, or exposed wire. Do not use a cable with visible damage.
- Clean the charging contacts. On a cordless unit, unplug first, then wipe the contacts on both the cleaner and the dock with a dry cloth. Remove any white mineral film gently.
- Give a flat battery time. Leave a deeply drained cordless cleaner on the charger for an extended period before judging it dead. A slow trickle can take longer than a normal top-up to register.
- Confirm charging indicators. Watch for the charge light or display to change state when connected. No response at all points to the supply, the contacts, or the battery rather than the electronics.
- Test the power supply separately. If your model allows, try a spare or replacement power brick, since a failed transformer is a common and low-cost point of failure.
Storage habits that cause this
- Long off-season storage without charge. Batteries left empty over winter can drop below their wake point. Store cordless units partially charged and top them up periodically.
- Heat exposure. Leaving the unit or its power supply in direct sun or a hot equipment shed shortens battery life and stresses the charger.
- Wet connectors. Plugging in before contacts are dry invites corrosion. Let everything dry fully before charging.
When it is the cleaner, not the pool
If the outlet is confirmed live, the cable is sound, the contacts are clean, and a cordless battery has had ample time on a known-good charger with no response, the problem has likely moved inside the unit. Signs of an internal fault include a battery that will no longer hold any charge, a power board that shows no lights under confirmed power, or a unit that clicks or buzzes but never starts. A battery at the end of its service life or a failed charging circuit are both plausible at this stage, and either may cost enough to weigh against the age of the cleaner. For how these units are expected to behave and where their limits sit, see our coverage of robot pool cleaner autonomy, and follow reliability signals and recalls on the Tracker.