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Hot Key/ Ignition

My husband and I recently test drove a used Nissan Sentra we’re interested in buying. When I removed the key from the ignition, it was burning hot, along with the metal circular area you insert the key. We only had a short test drive (about 10 minutes). Does anyone know what would cause such a thing to occur? Is this something that should cause me to say “no” to this purchase?

That’s strange indeed…In most cars, the actual ignition switch is located at the base of the steering column, between the brake and clutch pedals…A rod connects the key lock to the switch. The key-lock seldom has any electrical connections unless the vehicle is equipped with a “smart-key” anti-theft system…So the reason for the hot key is indeed cause for concern…

Not in most Jap imports. The switch is attached to key cylinder. This sounds like there’s a bad contact problem with the switch that will need warranty repair. BTW, there are better cars out there than the Nissan Sentra.

I don’t have a wiring schematic handy for this vehicle so I’m speaking in a general sense.

Some vehicle accessories such as the cabin blower motor, etc. are often run through the electrical part of the ignition switch and are not run through a relay. A relay is in essence an on/off switch. The relay allows the current used by the blower motor or whatever it may be to bypass the ign. switch and go through the relay instead.

When an item like a blower motor starts wearing and going bad it draws more current than normal and this current is pulled through the ignition switch. Over time this increased load can burn the electrical contacts.
This causes overheating and can cause the vehicle to quit running or even catch on fire in a worst case scenario.

I would want that problem solved before buying the car.
It could simply be an ignition switch with worn/burned contacts or it may have something else contributing to the problem.

Keys can often be very hot after being in the cylinder of a car with a very hot cabin. Was it a hot, sunny day? The question is was the cylinder hot before you drove the car.

Though this problem can be fixed I would pass on this particular vehicle since it is a new car. Somehow electrical current is passing through the key slot and causing it to heat up. Not a good thing.

I’m having the same problem in my 2002 nissan sentra. I’ve also had a short that killed my factory radio and my car horn. My horn Is also completely dead. I believe it to be a problem in the pad/wheel because I’ve eliminated every other possibility (new horn, fuses, relays, etc.) What to do, what to do…