If your Dreame handheld vacuum has issues charging with error 7,
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| Dreame charging error 7 |
The fix is to disassemble the battery pack and then and check the voltage of each cell with a multimeter.
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| Remove the screw at the handle near the charging port |
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| Remove 2 screws from the bottom of the battery pack near the bin |
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| Remove a screw from the other side of the battery pack |
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| Pry open the battery pack cover from the front as shown above. |
For example, the V11 has 7 battery cells so you will need to check all 7 of them.
Each cells need to be of similar voltage of about >3.6V. The best charger to use to charge the affected cell(s) is a magnetic USB battery charger that can charge 18650 batteries as you do not have to pry the cells apart which will damage the connectors.
Once the affected cell(s) has been charged up, you can pre test the battery pack by attaching the battery to only one part of the cover that will go into the motor assembly. Once you confirm there's no more error when charging, you can assemble back everything as before.
