Ignition Key Hot!

[waf102]

Searched but couldn't find any reference to this...

When I turn off the car and pull out the key I notice that the metal part is quite hot. Been that as long as I can remember.

But...listening to a caller on Car Talk (had a Subaru Forrester)...Click and Clack said she had a problem.

I always assumed (bad idea) that the key was completing a circuit and this was just resistive heating...part of the theft deterrent system.

I hate electrical problems (hard to diagnose, and usually expensive)...but if there's an issue I want to know!

Thanks in advance...

-Bill

[1990LS400]

Surely you haven't stooped to trusting Tom and Ray! (I also heard them this morning and rarely miss their show.)

Could your car have the rare ignition key warmer option? :whistles:

Speaking of "Car Talk" a reasonable answer to this question is from BustedKnuckles on the Car Talk forum: http://community.cartalk.com/discussion/118613/hot-key-ignition/p1

[steve2006]

The LS400 key does indeed have a blade heater, this should only operate when the ambient temperature is below 32 degrees and is to assist entry into the car if the door locks have frozen and the remote locking/unlocking has failed.

If the key blade heater is on all the time there must be a problem with the temperature sensor in the key fob and also this will reduce the fob's battery life.

You could take it to a Lexus dealer for repair but the cost would be high so have a look on ebay for a good used key.

:lol: :lol:

[1990LS400]

The LS400 key does indeed have a blade heater, this should only operate when the ambient temperature is below 32 degrees and is to assist entry into the car if the door locks have frozen and the remote locking/unlocking has failed.

Steve, was not the key blade heater only on LS400's with the optional electrically heated hub caps?

Seriously, I drove a 1990 LS400 from new to 183,500 miles for 13 1/2 years and my ignition key blade never got hot.

[curiousB]

Well since it's not April 1st I'll assume this was a serious post.

Let's think about it. Car sit in sun. Internal temp reaches 120+ degrees. All items in cabin warm to that temperature. Owner jumps in. Turns on AC and air cools off in 1-2 minutes. Steel steering column and key mechanism stay the 120+ degrees for quite some time due to thermal mass and "insulation factor" of plastic coverings. Heat transfers efficient to metal key blade. Mystery solved....

[landar]

While I realize that Steve and Jim are in jest (like usual ), think about how much current would have to flow through the key blade resistance (essentially milliohms) to cause that kind of heating. The fuse would blow before that point...BTW, just how MUCH heating is going on? Its all anecdotal at this point. If the car is running fine and you cannot light your cigar off the key, then its a non-issue.