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My wife drives a 2001 Buick Century with ~130k miles. A few days ago, she was driving it home when she described that several warning indicators came on suddenly, the windshield wipers stopped functioning, and she began to hear a winding noise. The car continued to drive home and when I opened the hood to look at it, I could smell a burning smell like an electrical fire. The car now does not hold an electrical charge for more than a few hours, but if I jump start it, it will run normally for at least a short period of time. I also checked the OBD2 fault codes and it reported P1404.

At the time, we were just about to buy a new car so we went ahead and bought one. This car now sits in the driveway as I try to sell it. I estimate it's not worth much more than $900, so I'm looking for suggestions on how to diagnose this car myself with minimal investment to see if there is a potential DIY fix that would make it more attractive to potential buyers.

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When the alternator fails, the copper windings melt and become shorted. This will cause an electrical fire smell and will cause several indicators to come on. As others have stated, burnt fuses and failed regulators can cause the same smell.

When a regulator stops... regulating, your voltage can spike to excessive levels causing equipment to burn out and fuses to blow.

However, since you mentioned that the wipers quit working, I'm assuming it was raining when this happened. If you live in a place that salts the roads in winter, rain water can become highly conductive, and hitting a deep puddle can send this water up into the engine compartment. Most of the electrical equipment is protected in sealed cases, unless these seals have worn. But the alternator and, consequently, the regulator are not protected. My first inclination is that the regulator failed or was temporarily shorted and caused the alternator to continue charging above 14 volts. At night, the driver might have noticed headlights and interior or indicator lights becoming excessively bright just before the problem occurred.

This situation is rare and circumstantial, but possible.

I'd like to reiterate, though, that it's normal for a simple alternator failure to cause an electrical fire smell, and for things like wiper motors to stop running, and also for several indicator lights to come on, chiefly the Battery Charging System light. When an alternator fails, you'll see black soot all over the vent holes where you can normally see the copper windings.

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P1404 is the error code for the EGR valve (exhaust gas recirculation).

From the symptoms you describe, however, I'd suspect you have a short circuit somewhere - you need to locate this before you can fix it - the best way of doing this is with a multimeter and a wiring diagram for the car (which you should find in a workshop manual).

Charge the battery and remove the fuses, and connect the multimeter in current mode between the battery and the car - DO NOT start the car like this, you'll destroy the meter!

Replace fuses one at a time until you see a current register on the meter - this will tell you that which circuits are drawing current - when you get one that shouldn't be, you've got your culprit...

The battery will probably need replacing, they don't tend to survive being repeatedly fully discharged - but don't do so until you've fixed the problem or you'll just destroy the new battery!

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Good advice, I'll report back after I've had a chance to do this. It may be after the 4th of July weekend. – kjgregory Jul 2 '14 at 14:56

I've had a similar problem. Alternator voltage regulator failed and the alternator was overcharging. Freaked out the car electronics and fried the battery. Replaced alternator and battery and all was well in that case, HOWEVER, wiring damage could also occur, which may take pulling the harness and inspecting the wiring (which I've also had to do after having an actual electrical fire after a fuse failed to break a shorted connection).

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