Question about 2003 Ford Focus

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Battery overcharges and light is on

Last year I had my alternator replaced. My battery light came on soon after and has been on ever since. A mechanic shop told me that the battery overcharges to 15.2 when is should be between 13.5 and 14.2. I need to get my car inspected next month and don't know what to do?

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Never saw a charging system problem cause anyone to fail inspection. But, overcharging will cook the water out of your battery and can damage the computer system if not taken care of. Overcharge can be caused by either a grounded alternator field wire or a bad regulator. Since the condition appeared after replacing the alternator it too is suspect as an internal grounding can also cause that.

Posted on Jul 20, 2009


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Posted on Jan 02, 2017

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SOURCE: charging

Most likely it is the voltage regulator that's going bad which allows overcharging. this is inside the alternator, so it most likely needs replacement. you could pull it out and take it in to most auto parts stores and they would check it to make sure.

Posted on Jul 06, 2009

  • 20 Answers

SOURCE: alternator overcharging

ok, there is an earth wire between the engine and the body (usually bolted to the exhaust manifold), you need to undo it from the body, and with a piece of sandpaper or a file, you need to clear away the paint from under where the wire connects to the body, (might be a bad earth giving a faulty sensor reading, because on the production line the body is painted before anything else is fitted), clean the end of the earth wire contact and re-connect.

if you still have the same problem, you need to see an auto electrician or your nearest dealer.

Posted on Dec 03, 2008

  • 1 Answer

SOURCE: My bumper is scuffed and

I had that same thing I went to the Nissan Dealer and bought some touch up painr and it worked good

Posted on Dec 09, 2008

  • 16 Answers

SOURCE: shop replaced the alternator, but

Look for loose or dirty connections. Could be a poor ground connection or could be poor connections at the battery. Clean the battery terminal connections.

Posted on Sep 08, 2010

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Put a new alernater an still over charging

Over charging could be the result of several things including:
    Faulty Voltage Regulator
  1. A car's battery will overcharge if the voltage regulator isn't working correctly. A voltage regulator is usually part of the alternator, and is used to keep a steady flow of voltage to the battery. If the voltage regulator is defective, it will send either too little or too much charge to the battery. If it sends too much, the car battery will overcharge. The voltage regulator is easily replaceable at an easily affordable price, sometimes for as little as twenty dollars, as of 2009.
  2. Faulty Alternator
  3. Sometimes the alternator itself can be at fault. The alternator is the device that converts the mechanical power of the engine into electrical power to charge the battery. When an alternator breaks, it usually stops creating electricity for the battery, which will then eventually die. However, if the wrong alternator is placed in the car, or if the alternator is running at the wrong pace, it will create too much energy for the car battery, causing it to overcharge. The alternator is another easily replaced part.
  4. Incorrect Charger Use
  5. If a battery charger is used to charge your battery outside of your car, improper use of the charger can result in overcharging. If a battery is placed on the charger too long, it can result in overcharging, and a significant decrease in your battery's lifespan and efficiency. This is why it is important to read about your specific battery and understand how long it needs to charge to be effective. Too much charge will lead to problems.
  6. Faulty Battery Chargers
  7. Sometimes chargers can be faulty. Their settings may be wired incorrectly, or the charges labeled incorrectly. As a result, your battery may be getting overcharged, even if you are carefully monitoring your charging. This is a problem that is hard to avoid, as manufacturing mistakes can happen anywhere, anytime without warning. It is a good idea to test your charger regularly to see if it is running correctly.
  8. Heat
  9. Extreme heat in the summer can also have an adverse effect on the car battery. If the battery has been previously overcharged, extreme heat can increase the problems caused by overcharging, and exacerbate any other problems with the battery. This problem can be hard to avoid if you live in a warm climate. The only real way to ensure safety against this problem is to avoid overcharge in the first place.

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