I used a 2 Volt automotive battery charger to top up my stock battery because I wanted to ensure the battery has a full charge before the cold weather arrives. When I connected the charger I didn't disconnect the battery from the car. I verified the polarity was correct before I plugged-in the charger.

I'm wondering if it's possible the charger caused a fault in car's electrical system. I'm concerned because when I started the car after charging the battery I switced on the fan and noticed the "AC OFF and Air-Recircultion" LEDs flashed red a few times and the climate control fan wouldn't run. After I turned off and re-started the car the climate control system worked normally and I haven't noticed any problems since.

Is this normal? This is the first electrical problem I've noticed with the car. Is there anything else I should look out for in terms of electrical problems? All the fuses look okay and all electrical systems appear to work properly. Does Volvo recommend disconnecting the battery terminals from the car when charging the battery?


All feedback is greatly appreciated!