Bad Alternator or Battery: Which One Is It and How Can You Tell?

A common mechanical issue in starting problems with most vehicles (especially with older models), is whether the behavior is due to a bad battery or a bad alternator. Since the two are inextricably linked this can be hard to determine sometimes. 


A strong battery will run a car for a time if the alternator goes out, but it does all of the work originally designed for the two to do together. If the battery dies however, then the car goes nowhere. Both problems are equally important and require immediate fixing. Yet, it can be confusing to know which one to fix over the other, so here is a guide to assist on some of the more common issues from the battery or the alternator.


If the current battery in your car is old, it might show signs of corrosion in the form of battery fluid leaking, there might even be a strange odor wafting through the vents that smells acidic. New batteries last approximately 3 to 5 years, but you have to calculate the amount of travel made within months to years, as well as the weather conditions of an area. Other factors of a failing battery can include; no dinging sounds or interior lights coming on when the door is opened. Loose connections in the vehicle's operating systems are a sign of a poor battery, as well as slow, sluggish starting when the ignition is turned on. Then of course, the car can be jump started, that's a pretty definite indication it was the battery.


On the other hand, if it happens to be the alternator that has seen its better days, then you could find out for sure from these following issues. Do the interior lights flicker, fade out, or brighten after a time? Are there any issues with the stereo, does the car stop and stall immediately after starting? If there is a squealing sound coming from under the hood that intensifies once the car is in motion. Has the battery failed because it was having to do all of the work originally designed for two? Does something under the hood smell as though it's burning (this may be due to seared or frayed wiring inside the alternator). 


If you are experiencing any battery or alternator problems with your car, then please drop by TOS Auto Repair today, as we would be happy to get it fixed for you.

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