Cordless vacuum battery won’t hold charge or charge at all (Dyson & Shark)
✅ Safe to check yourself
This is a common, low-risk check most people can do safely. Always unplug the appliance (or isolate power) before touching internal parts.
A cordless vacuum that won’t charge, or runs for a much shorter time than it used to, has a few genuinely common causes worth checking before assuming the battery itself needs replacing.
What to check first
- Check the charging contacts on both the vacuum and the dock/charger for dust or fluff build-up — a layer of dust here is surprisingly common and can prevent a proper electrical connection even when everything looks “plugged in” correctly.
- Check the charger’s plug and socket with another appliance to rule out a dead socket or a faulty charger cable.
- Check the vacuum is actually seated correctly and fully on its charging dock, not resting at a slight angle.
- If runtime has gradually shortened over a year or more of regular use, this is normal battery ageing (like a phone or laptop battery) rather than a fault — lithium-ion batteries lose capacity gradually over hundreds of charge cycles.
When to call an engineer or buy a replacement
If the contacts are clean, the charger tests fine on another socket, and the vacuum still won’t charge at all (rather than just charging to a reduced capacity), the battery pack itself has likely failed and needs replacing — a straightforward part on most models, and often user-replaceable without needing an engineer.
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