My 1998 Intirigue key won't turn th car off. Only goes to accesories so my battery ran down. How do I replace the ignition switch or is that the problem?

That wouldn't be a computer problem , maybe be the ignition switch . If you don't know how to test automotive electrical circuits , viewing wiring diagrams an using a DVOM - digital volt ohmmeter your best bet , have a qualified repair shop check it out . More then likely just a electrical connection problem , Voltage drop testing on main power circuit's is what needs to be done.
Free wiring diagrams here http://www.bbbind.com/free-tsb/ Enter vehicle info. year , make , model an engine . Under system click on electrical distribution , then under subsystem click on power distribution . Click the search button then the blue link. Start at the beginning testing battery connections , cables . Power supply to the fuse boxes ,to the ignition switch , an from the ignition switch. There is battery voltage to the ignition switch ,hooking up a test light or voltmeter to that main battery power feed an turning the key to run start etc... does the light go out or stay bright ?
Check out put from the ignition switch , start , run circuit's
https://www.youtube.com/watch?v=SO-eKuhCOqc

https://www.youtube.com/watch?v=efKoWifdcag

What about with the key in the on position -do the warning lights and gauges turn on? That would mean the ignition switch has power and can turn on.
Any theft alarm activated, immobilizing the car?
Won't turn over- you mean won't start or the starter won't spin the engine over? If it won't start, ignition spark or fuel problem. If the engine won't crank, problem is in the start circuit- from battery to starter, and from battery to ignition switch to starter. Park/neutral safety switch is in circuit between key switch and starter.

If the security light keeps flashing,you might as well do a reset.
Be sure to turn off all the accesories including the radio before you start the process.
Insert the key to the ignition switch and turn the key to ON position without starting the car.
leave it ON until the flashing light (security) stops.It will take approximately 15 to 20 minutes.
As soon the flashing stop,turn the key to OFF
position and start the cart.
Hope this help.

I know in the newer versions of the Bravada, Trailblazers, Envoys, the ignition switch itself is always the culprit. Not the switch the key goes in, but it's located under the steering wheel column. I know how to replace the newer ones but not yours. That's the first place I'd look.

If the accessories remain hot after you "remove" the switch the tuere is a short in the wiring between the positive and the acc. wire

your ignition switch is more than likely worn out.this is usually the only cause for this. you need to have the switch replaced.

replace the ignition switch ( inside the steering column )

Ignition switch?

I ran into this once also, and I remember that I just disconnected the battery for about half an hour.

Try that if you haven't already.

Do you have a Chip in the Key? if so that Could be the Problem,Ya see the chip is a resistor and if it looses its ELECTRONIC VALUE in its Case Resistance it wont start to test this Turn the Key in the ON posission then do the Screwdriver thing If it Starts Key is Good and Most Likely the Ignition (SWITCH) is Bad <<ELECTRICAL Side NOY LOCKEST SIDE For More Info Recontact Me
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