Sony HDR-CX440 How To Use Manual page 166

The POWER/CHG (charge) lamp does not light while the
battery pack is being charged.
Turn off this product.
Insert the battery pack to this product correctly.
Connect the power cord (mains lead) to a wall outlet (wall socket) properly.
The battery charge is completed.
[187] Troubleshooting
The POWER/CHG (charge) lamp flashes while the
battery pack is being charged.
When the battery is being charged using the Built-in USB Cable, disconnect the
Built-in USB Cable and connect it again.
If the temperature of the battery pack is too high or too low, you may not be
able to charge it.
Insert the battery pack to this product correctly. If the problem persists,
disconnect the AC Adaptor from a wall outlet (wall socket) and contact your
Sony dealer. The battery pack may be damaged.
[188] Troubleshooting
The remaining battery power is not displayed correctly.
The ambient temperature is too high or too low. This is not a malfunction.
The battery pack has not been charged enough. Fully charge the battery again.
If the problem persists, replace the battery pack with a new one.
The indicated remaining battery power may not be correct depending on the
environment in which this product is used.
[189] Troubleshooting
The battery pack is quickly discharged.
Troubleshooting
Troubleshooting
Troubleshooting
Batteries/power sources
Batteries/power sources
Batteries/power sources