98 ford ranger electical problem

johnnyxxljohnnyxxl Member Posts: 5
edited March 2014 in Ford
battery drains when headlights on in about 15 minutes while engine is running. The problem has been traced this far after a new alternatior and battery have been added/replaced. the wiring from the alternator and battery have been checked and nothing else is running except the clock on the radio. aside from the required things like the fuel pump etc. the battery doesnt drain while off, or while on without headlights. This has led me to think the problem is in either the computer for the vechile or a wiring defect some place any suggestions before my scheduled trip on the 30th at the garage???
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  • 0patience0patience Oregon CoastMember Posts: 1,712
    If they were replaced because the battery was going dead, they you probably wasted your money.
    I'd have to check, but I think you have an external regulator on your vehicle, if so, the regulator may not be working properly.
    Did they check to see that the alternaotr or charging system is working properly with a load?
    Sounds to me that whoever is working on it is lost. May want to find a qualified person to work on it.
  • johnnyxxljohnnyxxl Member Posts: 5
    The altinator has an internal regulator in this model and the altinator was burned out and only producing 20 amps of power on the testor, I am the one that had it tested and pulled it out and the battery was good at least initially. I live in an area where there are only a few mechanics aside from the dealership. And no I am not taking a vechile to a dealership to be serviced if at all possible so I have a one week waiting period on taking the vechile in to be checked and diagnosed at 45 per hour to look for a problem not even necessarily fixing it wish I could be paid for troubleshooting like that

    shadetree mechanic
  • 0patience0patience Oregon CoastMember Posts: 1,712
    What is the alternator putting out at a load?
    Meaning, with the headlights on, what is the alternator putting out?
    Did you replace the alternator yourself?
    If you did, was the battery disconnected before you installed the alternator. Some may think this is a dumb question, but I've seen many people try and replace an alternator without disconnecting the battery, only to fry the diodes in the new alternator.
    How is the alternator being tested? Is there voltage to the signal wire on the alternator?
    If the alternator doesn't sense voltage to the signal wire, it won't charge.
  • johnnyxxljohnnyxxl Member Posts: 5
    I pulled the battery when I installed the new alt. Now as to right now this one is puttting out about 95 to 98 amps at full draw which is where it should be and the test is an in machine one done with the equip at advance those guys are lifesavers. the draw with headlights I dont know because it runs the battery dead in less than the time it takes for me to get home from advance auto. would take me bout 15 minutes and the draw would cause the battery dead in bout 12. I always disconnect the battery when I work on my vechile since I already shocked the crap out of myself with a starter once. hard lesson but well learned. I am not sure what else can be the cause I am going to check my light switch tomorrow if I cant get it to a shop since I am off work and was referred to a shop that wont charge me for anything thats not real work so he wont charge me for trouble shoooting and locateing the problem unless he cant find the cause. thank the lord for honest people.

    shadetree mechanic.
  • 0patience0patience Oregon CoastMember Posts: 1,712
    It sounds like you have a short in the light system.
    In orcer to find out, you will need to find out how much the lights are pulling from the battery.Try disconnecting the headlights bulbs, then start the vehicle and turn on the headlight switch, does it still drain the battery?
    If it does, you eliminated the headlights bulbs as the problem. Then remove the tailight bulbs and reconnect the headlight bulbs and retest.
    hopefully you can see the direction of this and test until you locate the problem component.
    Godd luck.
  • spokanespokane Member Posts: 514
    I agree with Opatience. With the extreme short that you apparently have, you may also want to try operating the headlights for about two minutes and then feel all the connections/wiring in the lighting circuit to see if any are hot to the touch. This is not scientific but, with the extreme condition you have, it may help. If you don't have problems when the parking lamps are on, you have already narrowed it down to the headlight circuit only. Please let us know what you find.
  • wtd44wtd44 Member Posts: 1,208
    johnnyxxl-- Please let us know. Inquiring Ranger owners want to know! Mine is a '99.
  • johnnyxxljohnnyxxl Member Posts: 5
    I broke down and went to shop spent two hours watching it get tested, for 20 dollars found the fuse box had a fuse that was tight on one side and loose on the other he pulled the box tightend the socket wam bam thank you mam
    now I feel stupid.

    he found the problem with a circut tester with like 12 feet of wire on it. if I could have tested that long a circut maybe I would have found the circut with the problem.lol
    well the guy was nice bout it 2 hours and a simple problem 20 not bad
  • wtd44wtd44 Member Posts: 1,208
    That's good news, but you'd never have gotten the hood latch popped in my town for that price, let alone 2 hours of testing. You better buy that guy a present, or something!
  • spokanespokane Member Posts: 514
    Glad to know it's fixed. Don't be disappointed in yourself - this type of problem can be hard to find. In addition to the loose fuse holder, there had to have been a short circuit. I presume that he corrected the short when he reworked the fuse box.
  • bmaigebmaige Member Posts: 140
    I'm glad you found the problem and got it corrected. There is nothing any more aggravating than a short you can't locate. After reading down the list of posts I was going to suggest you pull the fuse on your light circuit and see if that prevented your leak down, and if not, try another one until you isolate it. Once a short is isolated to a ciruit it is a little easier to find and fix. Slow but can be effective.

    I have a 1988 Cadillac Brougham that only has 74,000 miles on it. It drives like a dream, but the alternator light glows faintly when I'm driving it, and the battery leaks down if it is parked very long. The alternator and voltage regulator have been checked and found to be all right, but I notice when I pull the headlights on the digital clock on the radio dims, so I suspect it is in that circuit. When the weather gets cooler I'm going to see if I can find it and fix it. If not I'll resort to my favorite independent mechanic.
  • bolivarbolivar Member Posts: 2,316
    This is usually an indication of bad diodes in the alternator.

    Don't know who/how checked it, but I bet you have a bad alternator.

    Why mess around with it when you could have a dead battery at any time because of this?
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