Problems with 93 Lincoln Town car Alternator?

The battery light came on while I was driving so I figured the alternator was out. We changed the alternator and checked the voltage on the battery which was 12.3 volts. The voltage with the car running was 11.7. I then took the alternator and had it tested which was good. I then changed the battery out and had the same results. Does anyone know what the problem may be. Is there a sensor that controls the battery light.



Thank You,

Clint
Problems with 93 Lincoln Town car Alternator?
On a 93 you will have an external voltage regulator... it will be the shiny metal box that the smaller wires from your alternator lead to... usually on the fender well as the guy said before me.

It looks like this...

http://www.performancepartsinc.com/image鈥?/a>



The reason the light is on is because your system is not charging right... your voltage is too low. With a good battery, and charging system... your voltage reading on the battery should be between 13.8 %26amp; 14.5 volts with the car running, and no electrical accessories on.



The regulator is what tells the alternator to charge, and how much to charge... they cost about $15 USD at any auto parts store, and are very easy to change out. Cheap and easy.



- Good Luck!
Problems with 93 Lincoln Town car Alternator?
On your inner fender is a voltage regulator, I believe this is your problem.
Well the light could be coming on simply bec there's too much draw on the system or it could be a short someplace or the regulator is shot.. Plus i am wondering if you checked the alternators output voltages bec that is low 11.7 Also just bec it tested okay on their test gig doesn't mean its a good alternator bec its not under a true load. Plus your cars battery should give out about 12volt and from the alternator it should be about 13.5 volts but if its up in the 15volt range the alternator is faulty.
11.7 volts of output is not good at all for this alternator. This is an undercharging rate for sure. All of my cars are putting out about 13.5 volts. Always keep in mind... a 12 volt system needs a little over 12 volts to run the car (AND) charge the battery.. The car does not run off the battery after it's started. It runs off the alternator. A good alternator supplying 13-14 volts, supplies 12 volts to the car and regulates the 1 or 2 extra volts back to the battery to keep it charged. It's simple. An alternator that supplies less that 12 volts is not even running the car... so how can it charge the battery??? I would go get another alternator. I think you got a bad one. (OR) if this ford still has a separate voltage regulator... that could be your culprit. The light on the dash will go out when you get the correct voltage to supply your car.
With the car running the voltage at the battery should of been 14volts. If it was only 12 I would be looking at replacing the alternator.If you were told it should be 12 volts, they were trying to sell you a bad alternator.