Battery dead, smoke coming from alternator

[MatthewM]

4 cyl 2010 Journey with 238,000 miles on it.  It's been cold in NW Ohio for the last week or so and the Journey would make a lot of whining sound for the first 30 seconds or so when starting in temps close to zero or slightly below zero in the morning.  This afternoon I started up the car with the key fob, went inside to say goodbye to the wife, then walked outside and noticed that the engine was off, but the fob was still in the ON position.  Battery appeared completely dead - no headlights, dash lights, etc.  Turned to the OFF position the key fob could not removed because the battery was apparently dead.  AAA came out and tried to jump it.  A wispy smoke emerged from what appeared to be the alternator; hard to tell because the AC unit is above the alternator and the smoke was coming up from the backside.  Of course AAA immediately disconnected the battery pack used to jump the car.  I will have it towed to a local repair shop in the morning but wondered if this points to the alternator or a short somewhere.  Both the battery and alternator were replaced maybe 3-4 years ago.  Thanks in advance.  Matt

[John/Horace]

Without using test equipment we would be guessing. If it was a remanufactured alternator 3-4 years ago, I would think it’s probably the cause.  Charge up battery first and load test it. Then run car and see what alternator does. Measure voltage loaded and unloaded etc.

There is a huge fuse that protects electrical system from bad alternator doing any damage.  Even batteries seem to last shorter than a few years ago. Lots of load with all the power options, most cars have 160 amp alternators now. Typical car in the 1980s was probably 80amps.

Edited January 22 by John/Horace