Hey guys, I encountered a strange issue with my 2013 ES last night.. Pulled in the garage, shut the engine off and noticed the flashing yellow triangle on the display and a message that said "key not detected". I waited awhile to see if it would go away but it did not.. so then I went back out to the car with my second key fob.. fired up the car.. shut her down and the Key not detected message was gone.. went back and got the first key fob - tried it out and everything was fine, again, no "key not detected" message... so I thought everything was good, just a glich right.. well about an hour later I go out to the car and I notice that the interior lights did not come on when I approached the car with the key fob ( the lights have always come on in the past when I got near the car ).. went thru all the settings, couldn't find anything, even messed with the light switch buttons on the front interior light.. got frustrated because I couldn't figure it out and went back in the house.. went back out a little later and this time, interior lights came on just as I walked up to the car... and slowly faded down after a few seconds when I closed the car door to go back in.. so right now everything seems to be working correctly but for the life of me I can't figure out why this happened.. fyi, I changed the batteries in both key fobs about 6 weeks ago and never an issue til tonight.. and of course, the warranty expired 3 weeks ago... any thoughts. Like I said, working fine right now.

Roland

 

Sounds like a fob battery issue. Maybe you installed a bad one?

 

That would be my first and easiest fix. If that does not solve your problem, is the original battery in the car. My wife's 2014 ES 350 UL was experiencing a myriad of minor electronic glitches including the one you described. Lexus dealer claimed that car battery was fine, but as we all know the ES 350 can be an electronic parasite. Last week, I took her car up to Sams Club and had the battery replaced (24-F Duracell $102.27 installed) and all glitches have disappeared. Besides the issue with the FOB, the presets for dash brightness, distance to empty after last refill and others are now working fine. Even reading text messages on the Lexus screen are back. Happy wife, happy life.

Remember the old expression, "winter may kill a battery, but the summer buries it".

Good luck,
Mark

 

I would think that was the case too, but I swapped out the batteries for some fresh ones in my key fobs in my 06 and every now and then it will still give me the warning. Usually when I have too much in my pockets at the time, between my phone, battery charger for phone, phone cord, pocket knife, work keys, car key, and what ever else I manage to have at the time, haha

 

First off, thanks to all of you for chiming in..and like all of you I think it's a key fob issue as well.. otherwise why did everything start working when I switched to my back up key fob..... and "right now" both key fobs seem to be working fine.. as far as the car battery goes, I just put a new interstate mtp-24f in the car less than 2 weeks ago, so I would assume that wasn't the problem.. for now I'll just keep an eye on it and hopefully it was just a glich. right now everythings good.. thanks again guys. I appreciate it.

Roland

 

Roland: I don't think this is a battery issue with fob or car battery, as you have ruled those out. I think it is a radio frequency interference issue, which by its nature is intermittent. All remote keys in cars must communicate between 275 and 450 MHz, which is allocated to them. The RF band is very crowded with hardly any band left open. The crowded band and other sources create opportunities for interferences. Did you or neighbor recently put up LED lights in garage? Those create electromagnetic interference in the 275 to 450 MHz (I know this because I measured it with an antenna and oscilloscope since it was messing up my homelink garage opener on my es, which runs at 315 MHz). There could be other sources generating interference. If your problem returns, change your LED lights to the ones that have a shroud with internal coating to absorb electromagnetic interferences.

 

DanZ.... This is interesting... as it turns out I actually put up new LED security lights all around my house.. however I did this back in the summer but never experienced the key detection thing til the other night. They're not motion sensor lights as they are controlled thru wall switches in the house ( got tired of replaceing motion sensor lights every 1 to 2 years ).. I mention that they are controlled by wall switches, and a couple of those lights are seldom used.. But it is possible on that night those lights were on.. Just can't remember - but yes, new led lights all around the house this past summer..

Roland