Yesterday I went to work just fine at about 8:45 in the morning. I got out around 4:30PM and went to start my car and nothing happened. The fuel pump wouldnt come on, the interior gauges didnt work and the power windows didnt work. When I would put the keys in the crank (highest) position, the tachometer would drop to about -300 rpm. The power locks worked so I thought ignition.
I bust out my toolbox and start taking off the column cover and lower the front two steering column nuts. I go to remove the ignition switch harness and the IGNITION SWITCH just breaks apart in 3 pieces of plastic. Im thinking "that's not good." An auto parts store is about a couple blocks away, I grab another ignition switch for $14. Pop it on, make sure the bar is aligned from the key cylinder. Put the keys up. Same result, nada.
I take out the volt meter and check my battery. Only 5.5 volts! No wonder. My dad gave me battery jump and the car turned over immediately. I drove it home and let it run for about 10 minutes. I started it today no problem and everything seems ok.
But Im wanting to make sure the igniton switch was the problem so I dont get stuck again. The harness that goes to the ignition switch was in good condition too.
Anyone who goes to change it, dont bother trying to take off the instrument cluster cover, just lower the two 9/16 nuts that hold the steering wheel. It will lower it enough to get the tamper proof torx bolts exposed.
Back to the original question:
Could a busted ignition switch drain the battery? I think what happened is, it got stuck in the on position and since I was away for 7 hours, it drained it almost completely.
I think you had a real good idea that you were on to the answer to your own question before you asked it. Most people who have lack of electrical power don't start looking for the answer by tearing down the steering column.
Yes, a broken on/off switch can drain a battery no matter which switch it is....even if it is the ignition switch. Yours sounded obviously broken, potentially leaving some electrical device(s) connected to the battery for 7 hours. You are indeed lucky your ignition system is not fried as stingrey suggests.
Now that you've replaced that faulty switch, are there any other power drains still active when they shouldn't be? Sounds like your voltmeter and another check of the battery in 7 hours will tell that.
I think you prolly found your problem.
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daughter owns '00 GT, bone stock, black on black, rag top
ghost, do you not have an ammeter in your car? that was the first gauge i installed, then was my oil pressure then my tach (have yet to hook up the oil pressure)
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89 fox, mostly stock, C&L 73mm MAF, bypassed coolant hoses to egr spacer, intake silencer removal, no a/c, all options but power mirrors?? blown cats, msd cap and rotor, bosch wires, autolite plugs, 5 inch auto gauge tach with recal and blue lensed shift light, PAPER FILTER I BOUGHT ONE!!!!!!! felpro gasgets on everywhere accept oil pan and a nice big classic mustang decal on my back window
Ghostdog do you know if that is the original switch?
Even though it was only $14, 1988-91 Mustangs has a recall on ignition switchs. I would try and get my money back.
I have no idea if it was the original one, it's in the garbage somewhere.
I have an autometer mechanical oil pressure and temp gauge that i need to install. They were in my vert' and I havent gotten around to installing them.
Just for your information. I have a 1988 GT and just recently had it in the dealer's shop for minor repair. They informed me of the ignition switch recall and scheduled it to be repaired the next day. So, yes there is a recall and even at this late date it is still valid. All you need to do is check with your local Ford Dealer.
Could a busted ignition switch drain the battery? 
, msd cap and rotor, bosch wires, autolite plugs, 5 inch auto gauge tach with recal and blue lensed shift light, PAPER FILTER 
