Laptop computers are one of the many items that we use that depends on a rechargeable laptop battery to keep it up and running. When your laptop fails to stay charged or to charge at all, it is time to troubleshoot the issue on your own before paying a professional. First test the charger to make sure that it is working properly.
You can test your HP pavilion dv4 battery charger follow the below steps
Be sure that the charger is plugged into a working outlet and getting power.
Try to run the laptop from the laptop charger only; if it will not run off the charger alone then the charger is faulty or no longer any good to power the HP pavilion dv5 battery. In some cases your laptop will run off the charger, but the charger will not be strong enough to charge the laptop. In this case you have a faulty charger.
Try charging your laptop with the laptop powered off. Sometimes the charger will charge the laptop when it is powered completely off, but not when it is on. If it only charges the HP pavilion dv8000 battery when the laptop is off, then you have a faulty charger.
Check the HP pavilion dv9000 battery for corrosion and/or leakage. If there is a sign of either corrosion or leakage you will need to stop attempting to use the battery pack and replace it immediately.
Test your charger with a voltmeter. If it is an AC charger of HP pavilion dv7 battery ,, set a voltmeter to 25 VAC. Make the contacts and probes touch, and look for a reading. If there is not a reading on the meter, the charger is not any good. For DC chargers, set a voltmeter to 25 VDC and make the contacts and probes touch. The meter should read at least 1V more than the chargers rating. If it does not, the probes need to be switched.
