xmate

The battery in my 06 DX Civic coupe died and I want to charge it using a trickle charger. I hooked up the charger and plugged it in. The red alarm light started flashing and an odd musical-like sound started coming from the stereo.

Anyone have any experience with this? Could you tell me what this means?

Thanks!

ezone

Do NOT have the key on while using a battery charger, especially if it is on a high charging rate..
You probably don't realize how many volts can come out of a 12v battery charger on high! You can RUIN stuff!

Radio shouldn't make noise unless it's on.
The beeper/warning chime speaker will though.

What you probably hear is a form of AC voltage (sometimes called ripple) from the charger coming through the electronics and the warning beeper. The battery charger sends it's power straight out of the transformer and through a rectifier, there are no filters or capacitor to clean up the voltage.


Car battery charger only has the first 2 units in the pics below, whereas a regulated power supply would have all 4 units.

xmate

I should clarify:
-the key is not in the ignition
-this sound is not from a radio station. The car is making the noise itself.

Is this a normal part of charging the battery? Or is this abnormal?

ezone

Shut the doors and turn the charger down to trickle charge. Is the noise still there?



It's probably normal, especially if the charger is set on high or boost. Chargers can cause a lot of electrical noise. And like I said, they can damage stuff.

Ideally, you should disconnect the cars battery cable before charging to protect the car, but that rarely happens.