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Q: Alternator went bad within a 24 hours of installing it

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about a week ago i noticed i was losing power while i was trying to start my car. when i got home it would not start. i replaced the alternator. not even a whole day went by and it was shot. i tried the disconnecting the negative battery terminal to see if the alternator would keep it running. it did not. i know the alternator is bad but im trying to figure out why it would go out in a day like that. i installed everything correctly. although i did notice yesterday while trying to further diagnose, that the power cable connecting to the alternator from the battery came lose and was barely connected to the power source. i did reconnect it with no luck. im affraid to put a new alternator in because i dont want to blow another one but i also have a feeling i may have been sold a reman dud. also, when i turn my turn signal on or roll down the windows, my stereo will flash and cut off for only the time i am using power in another source. also according to autozone my battery checks out fine

My car has 1830000 miles.
My car has a manual transmission.

Hi there. It definitely sounds like you may have received a defective alternator; it does happen. Also, have the battery fully charged prior to installing to prevent damage to the new assembly; there is usually a tag attached to new alternators stating to do this.

The loose terminal/cable would definitely cause erratic operation of electrical accessories as well. Recharge the battery and retest it, replace the defective alternator, and recheck the system and electrical accessories for abnormal behavior.

Have a professional mechanic, such as one from YourMechanic, assist you with an inspection of the electrical system and replace the alternator if needed.

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