It sounds like the battery is below the charging threshold. A LIon battery needs to be around 3.7V for the charger to kick in. We usually dismantle the phone and connect the battery to a 4.2V source with multimeter built in to see when it reaches 3.7V, usually it takes a few mins to get to 3.7V. Once this is done, you can connect the USB cable and charge normally.
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It sounds like the battery is below the charging threshold. A LIon battery needs to be around 3.7V for the charger to kick in. We usually dismantle the phone and connect the battery directly to a 4.2V source with multimeter attached to see when it reaches 3.7V, usually it takes only a few mins to get to 3.7V. Once this is done, you can connect the USB cable and charge normally.
It sounds like the battery is below the charging threshold. A LIon battery needs to be around 3.7V for the charger to kick in. We usually dismantle the phone and connect the battery to a 4.2V source with multimeter built in to see when it reaches 3.7V, usually it takes a few mins to get to 3.7V. Once this is done, you can connect the USB cable and charge normally.