ALT light comes on when car is off???

Discussion in 'Technical' started by spyguy, Jun 29, 2011.

  1. spyguy

    spyguy Member

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    It seems that electrical is going to be my theme lately:cry:

    Everything was great....I'd just replaced all four shocks, gave the Maverick a tune up, and was out running some erands. Car was running better than it ever has (while I've had it). Pulled into the garage, shut it off...and the ALT light came on.

    Don't have a my multimeter at home so I'm going to have to wait till tomorrow to start testing but I thought it was wierd that the dash light would come one ONLY when the car is shut off....keys out of the ignition. As soon as I start it up, light goes out and the car drives great.

    What gives???
     
  2. Bryant

    Bryant forgot more than learned

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    the alt light should come on when the engine is off with the key in the run or accessory positions. if its on in the lock position then i would suspect the ignition switch has a problem. it may just need an adjustment or need replacement.
     
  3. spyguy

    spyguy Member

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    LOL....Not bad, Thanks Bryant! I needed someone else to point me in the right direction...I was having electrical tunnel vision.

    Tuned the key past off, onto accesory and viola! light turned off....Turned it back to off and the light stayed off!

    Insult to injury..now the stereo stays on with ignition in the off possition and the key removed....lol. Looks like it's time for a new ignition switch. At least that's all it is.

    Much appreciated...now I can call it a night without worrying that it's gonna kill my battery or burn the house down after I give up for now.
     
  4. spyguy

    spyguy Member

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    Where's the switch?

    So it looks like it's the electronic ignition switch. Can anyone tell me what the trick is to access the switch? I've had the steering wheel off before and don't recall seeing it. Is there an easier way to get to in other than pulling the wheel and going in through the top of the column?
     
  5. rthomas771

    rthomas771 Member

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  6. spyguy

    spyguy Member

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    Fixed.....(Shh....don't tell the Maverick)

    Thought I'd close the loop on this incase anyone else runs into the same thing. It seems like every time I touch the car something else fails and requires attention. This time was no exception. It was however easier than I though and would have required less had I known what to look for.

    In the end, it turned out to be the voltage regulator.:D

    The first thing I did was replaced the ignition switch. It took two days waiting for the part to ship in, then alot more disassembly of the steering column and dash than I ever wanted to mess with. I did however find a few other goodies I'm guessing will need attention some time so it wasn't a total waste. The new switch (got it from NAPA autoparts for $43) seemed fine. After installing it though it actually seemed looser than the one I replaced and doesn't actually return the key back to the Run possition after it's started so I have to roll the key back after it fires or the starter continues to run. It does work though.

    Problem was, the voltage remained in the accesory (remote) circuit after the key is removed.....just like the old switch.

    Next I installed a new voltage regulator and the accesory circuit returned to correct function. I wish I'd just replaced the Voltage regulator in the first place and left the steering column alone. It would have been a $15 project and lasted 30 minutes instead of $60 and three days.

    I did end up with a spare igniotion switch and a better understanding of what's under the dash. Oh, and the electrical system functions properly.

    My suggestion to someone in the future would be to replace the voltage regulator first. It's the Cheapest potential point of failure....and if it's not bad now, you'll have a spare for when it does fail.
     

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