2 weeks ago, I installed a Delphi Roady XT XM satellite radio in my 2002 4WD 6 cylinder Hyundai Santa Fe. While installing the radio, I had the doors open and the lights on in the car. The whole procedure took about 2 hours. The next day, I noticed that the digital date display, which is included on the Santa Fe, was displaying the wrong date. When I went to start the car the battery was a bit sluggish but the engine managed to turn over. I guess by leaving the doors open and the interior lights on, I wore down the battery. I took the car for a short drive, then parked it back in my garage. When the engine is shut off, there is no power going to the cigarette lighter that runs the satellite radio. The next day when I tried to start the car, it was again sluggish but did start. The digital time had again reset itself to the wrong date and I had to reset it. The next day the same thing happened, so I unplugged the radio to be sure that there was absolutely no power going to it. It made no difference. The following weekend, my wife and I took a 3 hour trip to Connecticut. It was hard to start again, but when I tried to start the car the next day(after the 3 hour drive), it started immediately and the digital date worked fine. We drove the car 3 hours home the next day and the car continued to start fine until 2 days ago, when the same problem occurred. Upon starting, the engine would crank over slowly then start and the digital date display showed the wrong date again. The battery in the car is 3.5 years old. The temperature in my area is about 20 degrees Fahrenheit. Is it possible that I drained it when I originally installed the XM radio and that by driving 3 hours and back to Connecticut recharged it for a few days. Would this explain why during the short trips that we are using it for now, every time I try to start the car it turns over sluggishly, then starts? Once the car has started, it works fine and none of the accessories are working improperly. The headlights are bright, the wipers work fine etc. I'm thinking that I just need a new battery and hopefully not an alternator too. The battery light never comes on indicating a poor charge from the alternator. Thanks for your help.

From what you have said here it certainly sounds like you just need a new battery. My Old Mini Cooper used to have a very similar problem, but a quick battery replace fixed it fine.

A couple of tests you could do if you have a Multimeter. Check the voltage at the battery after the car have been run for a while. Should be 13-14 volts, at least with the engine reved up a bit. If not, the alternator or some connections are bad. I never had much trouble with the modern side terminals corroding, but the other ends of the cables including where it bolts to the body or engine can. Note, remove the negative terminal before messing with anything else. That way you can't short from a positive terminal to the body. Switch the meter to amps before you reconnect the negative terminal. With everything off, it shouldn't read more than a few tenths. If it does, it is possible while working on the radio, you may have accidentally created a problem somewhere.

Most of the more consumer friendly places will test electrical systems, but heavy pressure to replace what they find there.

Hi, Andyrose,
As another said, many auto stores will test the battery, (and the alternator) for you. Advance Auto, Pep Boys, others, will test the battery. Walmart also will test it for you.
At 3 1/2 yrs old, it's probably the battery. Best of luck, and Happy New Year.

You wouldn't lose anything by replacing a 3 1/2 year old battery.:cool:

Wouldn't hurt to put a higher cold cranking amp battery in it... 3 and a half years, like the others said, worth a try, its probably about dead, even had one myself a little over 2 years old... good one minute... the next... barely even spun the starter and wouldn't hold enough of a charge to keep the hood light on.

:) Thanks everyone. I had the battery replaced at Sears today and all is fine.

Great to hear it

Glad we could help