My wife’s 2002 VW TDI Jetta Wagon recently had the battery dashboard red battery light come on. My attempt to recharge the battery recognized that a battery failure was the cause. I had previous checked with my VW service people at my VW dealership to assure that any attempts to recharge wouldn’…

Yes periodic check is good and avoids alt. damage. Subaru recommends this check.

Yes. A defective battery can damage a perfectly good alternator. The alternators function is to recharge the battery once it’s been used to start the engine. And to keep the battery charged when various electrical systems are used in the vehicle. The alternator determines how much to charge the bat…

Furthermore, several of the auto parts stores will perform the tests of the battery and alternator in the car, for free. Just tell them you think you have a problem…perhaps, slow cranking.

The dead cell overworks the alternator, no matter how hard it tries, it can’t charge the battery…Alternators produce 3-phase alternating current. A “diode trio” rectifies (changes) this AC voltage into the DC needed to charge batteries. When ONE of the diodes fails (burns out) from overload, an “AC …

The only thing I will add to the good advice you’ve been given is that periodic testing is a good idea and should be performed a certain way. The battery should be placed on a charger for at least 30 minutes (preferably an hour) and a load applied to the battery with a carbon pile. The load should…

Actually, it takes two things to combine to damage the alternator, a bad cell and revving the engine. At low RPM the alternator doesn’t put out enough current, even to a dead short, to cause it to overheat and burn out the diodes. As you rev the engine, you also rev the alternator, increasing the …

You can replace a battery without “reset” worry by simply using a another 12VDC source to “jump” the battery connectors as the battery is replaced. A cheap source is a pair of 6V lantern batteries wired to provide 12 volts. A lighter plug can be used on the cord and plugged into the cars lighter soc…

This is no doubt a superior test method but typically, a home mechanic will not have this equipment nor the inclination to bring it to a battery store to pay for having it done. I use an informal (quick and dirty) test if there is doubt about the battery. Turn the headlights on and start the engin…

Even VWs, with their dealer only reset, can supposedly have their batteries disconnected for up to 90 minutes without making the car’s computer die. After that, you’re screwed. I got stung on a New Beetle a couple of years ago. It was dead when I bought it. A new battery allowed it to start and …

Does a Car Battery with a dead cell cause failures of alternators?

Maintenance/Repairs

Wha-Who October 28, 2007, 1:28am 6

There is a lesson to be noted here which is to not try to milk the last month of life from a battery, especially after the warranty has expired. Auto batteries, on a yearly basis for the warranty period, are cheap. I will check the ages of ours for sure now.

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Does a Car Battery with a dead cell cause failures of alternators?

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