Keyless entry woes

[Lex_utor]

I have keyless entry. My key fob is behaving on me. It was doing strange things a few months back and I changed the Battery and it fixed it. Now it's at it again.

The key seems to lose connection with the car and I get a key not found warning on the dash.

I stop the car, get out and I can't lock the doors. Not by pressing the button on the door handle, not by pressing the button on the key FOB. When I exit the car, it beeps 3 times in a similar way it does when you leave with the engine running. But now the engine is off. When I press the door handle button to lock it, it just beeps a long beep and doesn't lock.

Other times it just works as it should. 

Any ideas what could be? Can it be the Battery again? I just changed it a few months back. So I would think not.

I must say, I enjoy the car immensely and would have a hard time replacing it, so much I like it and all the boxes it checks. But I have never had a car with so many electronic related glitches, which suprises me, since it's a Lexus. It's my first Lexus though. So maybe this is to be expected, despite the famous reliability reputation.

 

Thanks a lot for your help as always. 🙂 

 

P.S. Is it just me or the traffic in this forum is slowing down quite a bit? Maybe most are indeed selling their IS.

[#Sandy#]

32 minutes ago, Lex_utor said:

I have keyless entry. My key fob is behaving on me. It was doing strange things a few months back and I changed the battery and it fixed it. Now it's at it again.

The key seems to lose connection with the car and I get a key not found warning on the dash.

I stop the car, get out and I can't lock the doors. Not by pressing the button on the door handle, not by pressing the button on the key FOB. When I exit the car, it beeps 3 times in a similar way it does when you leave with the engine running. But now the engine is off. When I press the door handle button to lock it, it just beeps a long beep and doesn't lock.

Other times it just works as it should. 

Any ideas what could be? Can it be the battery again? I just changed it a few months back. So I would think not.

I must say, I enjoy the car immensely and would have a hard time replacing it, so much I like it and all the boxes it checks. But I have never had a car with so many electronic related glitches, which suprises me, since it's a Lexus. It's my first Lexus though. So maybe this is to be expected, despite the famous reliability reputation.

 

Thanks a lot for your help as always. 🙂 

 

P.S. Is it just me or the traffic in this forum is slowing down quite a bit? Maybe most are indeed selling their IS.

 

[#Sandy#]

Just wondering if it has been an old or faulty Battery. Why not check the voltage of a replacement against the one fitted. It worked for me. I carry a spare Battery in the car just in case, best of luck.

[scudney]

Probably just a cheap Battery not up to the job lol, can say i have never had such a problem, tend to use duracell, varta,renata batteries which last a few years 🙂

[J Henderson]

Mobile phone masts, phones themselves, other RF equipment, WiFi etc have been known to screw with the signal.

[normski2]

+1 to the above comment. I had an episode some years back caused by a wireless doorbell.

What worked at the time was to pop the Battery out and put it back in some feet away from the doorbell.

[McShmoopy]

To be fair I was experiencing this for quite some time, I found that the batteries I ordered from amazon were the main cause. I believe the key fobs operate on a 3V CR123 Battery and over time if the Battery has been sitting around in storage they lose their voltage and drop to 2.9V. When that happens the key fobs tend to misbehave, not unlocking or locking properly even via keyless entry. 

Best way around this is go to Halfords or any retail store directly and get a Battery from there. Their batteries arent stored there for months and months unlike amazon so good chance thatll resolve your unstable key fob, this seemed to work for me.

I did get some RF interference one time on my estate when they were doing phone line works and had to park my car on the driveway else I couldn't open it unless I used the key blade! 

[SeanR]

My car told me the Battery in the fob was on its way out, a few weeks back so replaced it.

Is this not standard on previous years ?

[J Henderson]

Actually, that's right. You get a dashboard warning when the fob Battery is low.

[Lex_utor]

Thanks everyone. I didn't notice any warnings about low Battery. I will pay attention when it does it again. Otherwise, I will just replace the Battery again. I did buy it at a local store rather than online. The brand is renata.

[Linas.P]

To be honest it does not matter where you buy the Battery, what matters is that Battery does not spend years on the shelve until they lose their capacity. The risk of that happening is the same in halfrauds or anywhere else. If anything I reckon amazon moves magnitude more batteries so risk of them having old stock is much lower.

I would say just don't buy cheap batteries - I bought Duracell and it lasted for 3 years. Lexus original Panasonic batteries lasted for 6 years, problem is that most of Panasonic batteries you find are either fake or old stock and they are the ones causing most issues. Renata of all things belongs to Swatch Group, so they are watch batteries made by the same company as Tissot and Omega! They should be good, but my guess - either fake or old stock in this case. 

But as others said this is just characteristic to low key Battery, never happened to me when driving, but has happened when I had to walk-up right to the door handle before car unlocks and then having to press start key multiple times before it recognises and showing "no key warning". Touching the key to start button always helps.

This as well has happened right after Battery replacement - specifically by Lexus Dealership i.e. I was doing full service and brought both key fobs and told them to replace batteries (as it should be included). They were kind of surprised by request which didn't inspire confidence, but took them away and told me they replaced batteries. Main key fob was the one giving me an issue, the spare one was never used and as far as I know had good Battery. It was what I have used for few days when main one was misbehaving. That said I thought if one died then the other one will die soon. So anyway they replaced both batteries, but month later my main started misbehaving again and then spare one was completely dead. So what exactly they used to replace those batteries?! Nobody knows, but perhaps old batteries they had laying around?! Anyway replaced them with Duracell and key worked fine for years. 

By the way I am not saying that Duracell is some magic Battery, simply they are mainstream brand which doesn't sit around and therefore you get them fresh.  

[ColinBarber]

On 10/15/2022 at 8:56 AM, Lex_utor said:

I stop the car, get out and I can't lock the doors. Not by pressing the button on the door handle, not by pressing the button on the key FOB. When I exit the car, it beeps 3 times in a similar way it does when you leave with the engine running. But now the engine is off. When I press the door handle button to lock it, it just beeps a long beep and doesn't lock.

If you get a long beep when trying to lock via the door handle then it indicates one of the doors isn't shut or it thinks the key is still in the vehicle. When it does this look inside to see if the door open warning light is lit on the dashboard.

You don't have a spare key left inside the car do you?

Wrapped your centre console in something metallic that may cause the sensors to not operate correctly?

 

Worth changing the Battery - you should be getting a warning but maybe the one you have just cannot provide enough power for some reason. Make sure you get the right one and as Linas says above, give a genuine brand from amazon (dispatched and sold by amazon not a third party) so you have a chance of it not being passed its best before date.

[Lex_utor]

Alright. Thanks. It has not done it again so far though.