Hello! I gave a buddy a jumpstart today, he hooked the jumper cables to his car first then hooked to mine but when he did he hooked to mine backwards, only for a couple seconds while the car was running....now driving home tonight I notice all my lights are dim. When I accelerate they get back to normal but at idle they're noticeably dimmer. My stereo even restarted once. Is my alternator bad now? The battery light hasn't even flickered on at all....Thanks

 

sounds like a fried voltage regulator inside the alternator or bad battery also check the connections,(belt tension maybe?) if it is the volt regulator the alternator will take a crap on you pretty soon test with a multimeter

 

That's what I was afraid of as the alternator and battery are only 1 year old. Thank you I will test them