Battery is discharging

Discussion in 'Gen 1 & 2 - Electronics & Audio' started by SHOisfun, Jul 9, 2016.

  1. SHOisfun

    SHOisfun SHO Member

    Joined:
    Jul 16, 2006
    Messages:
    55
    Likes Received:
    1
    Gender:
    Male
    Occupation:
    Tooth doctor
    Location:
    North Carolina
    I'm having a problem with my battery going dead on my 93mtx. Ford has replaced it several times within 6 months but I think there is some type of short. Each time my radio ( new one ) needs to be reprogrammed. I noticed this time the the doors locked when I shut them or when I shift out of reverse into 1st. Strange. Seem to happen right after I had the fuel pump replaced. I also tried to read the code reader I bought. It came out 511 511 3 3. So it doesn't look like it read anything. (did hear everything click and run). HELP and THANKS!!
     
    Last edited: Jul 9, 2016
  2. luigisho

    luigisho SHO Member

    Joined:
    Nov 2, 2001
    Messages:
    7,314
    Likes Received:
    690
    Location:
    va beach,va
    Home Page:
    There could be problem with the electrical wiring for the pump or sender. Most common issue is usually the starter or the alt. There are how to videos on you tube for tracking down shorts. How much time do you want to devote to this vs ability to pay a pro car electric guy to probe and track it down? The original wiring is very old at this point so that can complicate things. I have noticed alot more posts about electrical issues over the past year or two compared to the last decade
     
    SHOisfun and SHOdded like this.
  3. sperold

    sperold Last to Know

    Joined:
    Aug 25, 2008
    Messages:
    3,106
    Likes Received:
    851
    Gender:
    Male
    Occupation:
    Mech. Tech.
    Location:
    Ontario Canada
    The monster connector on the drivers fender can give you trouble (C100, I think; the one with the bolt in it). It looks after the "always live" circuits in the engine compartment fuse box.
    Remove it from the fender and look at the hidden side where the wires fold-over and change direction. In my case the one wire had rubbed though and shorted. And another wire had turned green, swelled-up, and broke the continuity (even though when you pulled the wire it stayed together).

    The other thing you can do is: every night, take a different fuse out of the under hood fuse box and see if your trouble stops at a certain fuse.
     
    SHOisfun and SHOdded like this.
  4. luigisho

    luigisho SHO Member

    Joined:
    Nov 2, 2001
    Messages:
    7,314
    Likes Received:
    690
    Location:
    va beach,va
    Home Page:
    I have seen some of the youtube vids with a meter and looking for a draw and removing fuses to track down the circuit where the draw is coming from. It takes some time and an extra set of eyes/hands will help it go faster but you can do it yourself if you have enough time and patience
     
    SHOisfun likes this.
  5. SHOisfun

    SHOisfun SHO Member

    Joined:
    Jul 16, 2006
    Messages:
    55
    Likes Received:
    1
    Gender:
    Male
    Occupation:
    Tooth doctor
    Location:
    North Carolina
    Thanks so much guys. I'll give it a try and let you know
     
  6. SHOisfun

    SHOisfun SHO Member

    Joined:
    Jul 16, 2006
    Messages:
    55
    Likes Received:
    1
    Gender:
    Male
    Occupation:
    Tooth doctor
    Location:
    North Carolina
    So my SHO has sat for a while. Still having this short somewhere but I do notice that when I initially start it up and shift into 1st gear, the doors lock. Never ever noticed that before. Have anything to do with the short that is draining my battery?
     
  7. luigisho

    luigisho SHO Member

    Joined:
    Nov 2, 2001
    Messages:
    7,314
    Likes Received:
    690
    Location:
    va beach,va
    Home Page:
    My MTX cars never did that. It's been a while since I owned a GenIII but I think it might have had that feature. Earlier cars maybe not
     
  8. rubydist

    rubydist SHO Member Staff Member

    Joined:
    Jun 25, 2007
    Messages:
    6,235
    Likes Received:
    1,940
    Location:
    Denver
    I think your codes were actually 511, 511, 111, 111.

    The doors locking when you shift out of reverse is standard - if you don't want that you have to disable that feature. It will turn on every time the battery is disconnected.

    current drains are a real pain to find. Generally, you must remove one fuse at a time overnight to see if the battery stays up or still goes down, repeat until you find the right circuit. Then, you have to trouble-shoot that circuit to find the short. And, keep in mind it may be intermittent, so it won't necessarily do it every day...
     
  9. luigisho

    luigisho SHO Member

    Joined:
    Nov 2, 2001
    Messages:
    7,314
    Likes Received:
    690
    Location:
    va beach,va
    Home Page:
    My 93 manual car doesn't autolock when running. You sure that is standard?
     
  10. rubydist

    rubydist SHO Member Staff Member

    Joined:
    Jun 25, 2007
    Messages:
    6,235
    Likes Received:
    1,940
    Location:
    Denver
    if you read the manual, that is how they are supposed to work. in my experience, less than half of them actually do, but that is what they are supposed to do.
     
  11. sperold

    sperold Last to Know

    Joined:
    Aug 25, 2008
    Messages:
    3,106
    Likes Received:
    851
    Gender:
    Male
    Occupation:
    Mech. Tech.
    Location:
    Ontario Canada
    My 93 manual transmission car has this automatic lock (when shifting out of reverse).
    My 95 manual transmission car does not have this feature, and has never had it.
    And my 90 does not have it.

    I find it an annoyance on my 93, but I have not taken the time to disable the so - called feature.

    This has no connection to your battery drain.
    If it drains your battery in short-order, it should not take a very sophisticated meter to measure this loss.
    Concentrate on your under hood fuse box.
     
  12. SHOisfun

    SHOisfun SHO Member

    Joined:
    Jul 16, 2006
    Messages:
    55
    Likes Received:
    1
    Gender:
    Male
    Occupation:
    Tooth doctor
    Location:
    North Carolina
    Hey. Thanks for all the response!!

    Here is what I did. I took a volt meter and measured my battery to see if its good. It was at 12.4 volts

    Disconnected the negative to the battery. Changed the meter and leads to amps. Set it on 2 amp setting. Put red lead to the disconnected neg battery lead and red to neg post on battery to complete the circuit. Meter read .74 amps. Opened the door to the car and the amps went to 1. I pushed on the button at the door to turn the interior lights off. Pulled the fuses under the dash. All of them didn't budge the .74 reading much except fuse 8. (turns off the interior lights and I think radio? Don't really know. I did notice that if the interior lights were on and I pulled the 8 fuse the lights went off but I heard something run around the aftermarket radio when the fuse was put back in) That dropped it to almost 0 amps.

    So, I figure the car is pulling .74 amps all the time. Takes a weeks of just sitting there for the battery to be almost dead.

    What is 8 fuse?
     

Share This Page

If you wish to help keep SHOforum running, please click the donation button below