Starter stays on with no key on my 99 Avalon - 1999 Toyota Avalon

It sounds like you have a bad actuator. This is attached to the starter and has a solonoid that pushes the starter motor gears into the engine gear. If the solonoid is faulty this may happen. Also check alignment of the same.

this is caused by a bad starter, i would also check to make sure the battery connections are clean and tight, this is common on forgein cars, you get a click and as you kepp cycling the key it makes the connection inside the starter and starts, 99% of the time its a bad starter it will get to a point soon where it doesnt start anymore and you will get stuck. hope this is helpful.

I think you should go for repair manual first for your vehicle after that it will be easy for you to solve the problem. Check the link may be you will get something useful here
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Could be your starter, sounds like your starter soloinoid(pulls starter gear into flywheel) might be defective. First it will not pull gear in, then if it sticks in your car could keep starting even if the key was turned off .
without looking at the car I could'nt say how hard it would be to change. It has been my observation that newer cars are much more difficult to change

The blower motor switch or the resistors are defective.

Hello I have simular problem the ignition on is stuck in that position with the key turned off and out of the ignition switch.It feels like the key switch is spinning freely in the ignition. Do I need an ignition switch?

Sounds like either the voltage regulator or altenator is bad. Most part stores will test altenator, battery, and starter for free in the vehicle or out. Double check relays and cable connections

call the dealership with our serial number they will cut you a key that goes there just show proft ownership thanks .pierre

remove negative battery cable, remove starter bolts, remove the wires to it. Reverse proceidure to reinstall. Enjoy!

you have a bad srs relay, take it to autozone and tell them you want a trouble code done, it is free, it will tell them what it needs.