If I leave my key in the car…
Discussion
My car was old before it’s time when it was built in 2013. It’s more about loud noises than technology. Let us say hypothetically, I leave the keys in it when I park in my garage. If I buy a new car with keyless go and do the same, is there additional draw on the battery of either key or car?
In fact, do these new fangled keyless go keys need their battery changed more often as I imagine they are broadcasting all the time. Is it an issue for the spare? When my primary goes flat and I’m about to run out to work, I just grab the spare. Would I run an additional risk with keyless?
I ask because I am in a courtesy car with keyless go and it’s very likely my own car has gone to dealer for service/repair its final time before I sell it.
In fact, do these new fangled keyless go keys need their battery changed more often as I imagine they are broadcasting all the time. Is it an issue for the spare? When my primary goes flat and I’m about to run out to work, I just grab the spare. Would I run an additional risk with keyless?
I ask because I am in a courtesy car with keyless go and it’s very likely my own car has gone to dealer for service/repair its final time before I sell it.
I wouldn’t be leaving keys in a car for a multitude of reasons beyond the security aspect.
Keyless go keys/fobs/cards normally “go to sleep” if not near the car /moved so leaving them in the car is likely to run the their battery down.
More importantly, as I discovered with an ordinary key with a transponder in it, even cars without keyless go keep some systems live when the keys are in the dash - I was moving cars around and left the keys in one. Went to move it the next day and the main battery was flat because I’d left the keys in it even with ignition off.
Keyless go keys/fobs/cards normally “go to sleep” if not near the car /moved so leaving them in the car is likely to run the their battery down.
More importantly, as I discovered with an ordinary key with a transponder in it, even cars without keyless go keep some systems live when the keys are in the dash - I was moving cars around and left the keys in one. Went to move it the next day and the main battery was flat because I’d left the keys in it even with ignition off.
I'm finding that Keyless Go fobs need battery replacement annually or sometimes a message comes up on the dash that the battery is low, even if the fob is in or near the car. On most cars you can still use a depleted fob by holding it up to the start button.
On cars with the a standard plipper fob, I don't change batteries for around 3-5 years.
I change batteries in around 15 cars in our wider family and just buy loads of varying button batteries from Amazon.
On cars with the a standard plipper fob, I don't change batteries for around 3-5 years.
I change batteries in around 15 cars in our wider family and just buy loads of varying button batteries from Amazon.
Miserablegit said:
More importantly, as I discovered with an ordinary key with a transponder in it, even cars without keyless go keep some systems live when the keys are in the dash - I was moving cars around and left the keys in one. Went to move it the next day and the main battery was flat because I’d left the keys in it even with ignition off.
It doesn't even need a transponder. My car just has a key and if you turn off the ignition most of the cars electrical circuits stay live until you physically remove it from the barrel (however if you put the key in but never turn it, they stay off). RicksAlfas said:
You won't be able to leave a key in the car and lock it.
You get a message on the dash telling you when the key battery is getting low.
I just keep a spare battery in the glovebox.
(If it's a Mercedes they give you one at each service).
'Give'? Lol!You get a message on the dash telling you when the key battery is getting low.
I just keep a spare battery in the glovebox.
(If it's a Mercedes they give you one at each service).
My last Mercedes service bill shows 'Extra work for replacing battery for transmitter key' - 2 x CR2032 batteries, one of which was just left in the car, charged out a £13.50 and with VAT on top of that.
h0b0 said:
If I buy a new car with keyless go and do the same, is there additional draw on the battery of either key or car?
Some systems in the car may remain active with the key in range, but the draw on the key will be very low. I wouldn't leave it in or on the car.h0b0 said:
In fact, do these new fangled keyless go keys need their battery changed more often as I imagine they are broadcasting all the time.
They don't; the keys will be energised within a short range of the car and respond to requests (for keyless functions), or if you push a button send a request to the car, otherwise are powered down.h0b0 said:
Is it an issue for the spare? When my primary goes flat and I’m about to run out to work, I just grab the spare. Would I run an additional risk with keyless?
No.They take a battery every 2 years or so in my experience.
You can usually tell when they're getting low, They'll be a bit more sluggish to unlock, and have a dashboard warning in most cases.
They usually have a postion (near the start button or steering column) where you can waft the key if it has a dead battery too.
Leaving keys inside the car doesn't work, they'll throw a massive wobbly when you try to lock the car.
You can usually tell when they're getting low, They'll be a bit more sluggish to unlock, and have a dashboard warning in most cases.
They usually have a postion (near the start button or steering column) where you can waft the key if it has a dead battery too.
Leaving keys inside the car doesn't work, they'll throw a massive wobbly when you try to lock the car.
Thank you everyone. It seems as I suspect keyless cars are not a step forward for me.
I’ve had many as rental cars and my wife has one but she refuses to use the garage. I have found when we rent one the kids still run up to the car and I have to use the remote to open it so they can get in while I walk. No gain there.
I don’t leave the key in the ignition when my car is in the garage so no drain there. But, as others have said, if I do with the next car it will remain active for a period of time.
I currently have a courtesy car in the garage and the key in the house. I prefer not to bring the key in. If someone wants the car and has gone to the trouble of getting in the garage, I want them to take it without having to come in my house.
I have also not figured out how to open the boot from outside the car without using the key.
I’ve had many as rental cars and my wife has one but she refuses to use the garage. I have found when we rent one the kids still run up to the car and I have to use the remote to open it so they can get in while I walk. No gain there.
I don’t leave the key in the ignition when my car is in the garage so no drain there. But, as others have said, if I do with the next car it will remain active for a period of time.
I currently have a courtesy car in the garage and the key in the house. I prefer not to bring the key in. If someone wants the car and has gone to the trouble of getting in the garage, I want them to take it without having to come in my house.
I have also not figured out how to open the boot from outside the car without using the key.
Muzzer79 said:
RicksAlfas said:
You won't be able to leave a key in the car and lock it.
This.Each of the keyless go cars I've had have proximity sensors so they know the key is in the car.
The car then prevents you from locking the doors, to prevent you from locking yourself out.
I was prepping my 8-series to go back at the end of its lease which involved locating the booklet holder etc that the manual came in and which I'd removed from the glovebox for space reasons some two and a half years earlier. I found that and for convenience, chucked the second key in there too and left it in the kitchen for a few days. Once I remembered to take it out to the car with me I popped it in the glovebox....completely forgetting the other key was in it.
A week later I get a 'Key battery low' warning every time I get in the car to go somewhere. I swapped the battery in my key but kept getting the damn bonging noises and yellow warning triangle. I tried several different batteries, in the end I rang BMW and asked if there was some weird reset proceedure I should do. They said to try a 'BMW battery' for which I said they're taking the piss...but I bought one anyway.
STILL. BONGING.
It was only when I decided to try using the second key that I went into a panic as I couldn't find the f
king thing anywhere. I turned the place over and was about to resign myself to having to replace it at great cost when it clicked...It was the key in the booklet holder in the glovebox that was low and the car was - quite correctly - warning me of this every time I got in it. If my legs would bend that way I'd have kicked myself when I realised.
Changed that battery (and put the key back somewhere sensible!) until the car went back and all was well.
RicksAlfas said:
Good effort Funk!
Funk said:
You can have a keyless entry key in a car and lock it with the other key. Confession time...
Out of interest were you locking the car by pushing a button on the key, rather than the touch panels on the door handles?Funk said:
RicksAlfas said:
Good effort Funk!
Funk said:
You can have a keyless entry key in a car and lock it with the other key. Confession time...
Out of interest were you locking the car by pushing a button on the key, rather than the touch panels on the door handles?h0b0 said:
...
I currently have a courtesy car in the garage and the key in the house. I prefer not to bring the key in. If someone wants the car and has gone to the trouble of getting in the garage, I want them to take it without having to come in my house.
...
I don't want to sound harsh, but...I currently have a courtesy car in the garage and the key in the house. I prefer not to bring the key in. If someone wants the car and has gone to the trouble of getting in the garage, I want them to take it without having to come in my house.
...
You need to be very careful with that, if in the unlikely event your car does get stolen, I don't think the insurance company will want to pay out if you had left the keys in it, even if it was in the garage!
Olivergt said:
h0b0 said:
...
I currently have a courtesy car in the garage and the key in the house. I prefer not to bring the key in. If someone wants the car and has gone to the trouble of getting in the garage, I want them to take it without having to come in my house.
...
I don't want to sound harsh, but...I currently have a courtesy car in the garage and the key in the house. I prefer not to bring the key in. If someone wants the car and has gone to the trouble of getting in the garage, I want them to take it without having to come in my house.
...
You need to be very careful with that, if in the unlikely event your car does get stolen, I don't think the insurance company will want to pay out if you had left the keys in it, even if it was in the garage!
Crime in the US is very different to how it is perceived in the UK. Outside the usual hotspots crime levels are so low it allows people to live in a different way. Even after 20 years it surprises me. My kids ride their bikes to school and never lock them. I am from Manchester and I still would consider it my kids fault if their bikes got stolen because they are just offering them up to thieves.
Olivergt said:
h0b0 said:
...
I currently have a courtesy car in the garage and the key in the house. I prefer not to bring the key in. If someone wants the car and has gone to the trouble of getting in the garage, I want them to take it without having to come in my house.
...
I don't want to sound harsh, but...I currently have a courtesy car in the garage and the key in the house. I prefer not to bring the key in. If someone wants the car and has gone to the trouble of getting in the garage, I want them to take it without having to come in my house.
...
You need to be very careful with that, if in the unlikely event your car does get stolen, I don't think the insurance company will want to pay out if you had left the keys in it, even if it was in the garage!
Garages also attract the "low level" thieves after your golf clubs, power tools or lawnmower to sell down the pub for £50. They won't have gone there looking to take a car, but If they get in there and find a car with the keys in, they'll think "Bonus - I'll use that to take this stuff I've just stolen away in"
SkodaIan said:
Olivergt said:
h0b0 said:
...
I currently have a courtesy car in the garage and the key in the house. I prefer not to bring the key in. If someone wants the car and has gone to the trouble of getting in the garage, I want them to take it without having to come in my house.
...
I don't want to sound harsh, but...I currently have a courtesy car in the garage and the key in the house. I prefer not to bring the key in. If someone wants the car and has gone to the trouble of getting in the garage, I want them to take it without having to come in my house.
...
You need to be very careful with that, if in the unlikely event your car does get stolen, I don't think the insurance company will want to pay out if you had left the keys in it, even if it was in the garage!
Garages also attract the "low level" thieves after your golf clubs, power tools or lawnmower to sell down the pub for £50. They won't have gone there looking to take a car, but If they get in there and find a car with the keys in, they'll think "Bonus - I'll use that to take this stuff I've just stolen away in"
Muzzer79 said:
RicksAlfas said:
You won't be able to leave a key in the car and lock it.
This.Each of the keyless go cars I've had have proximity sensors so they know the key is in the car.
The car then prevents you from locking the doors, to prevent you from locking yourself out.
Does this apply if the engine is running?
Shortly after getting my Mazda 2 I started it to set it to defrost/demist the screen. Got out to scrape the ice off the side windows and couldn't get back in again.
All doors locked and spare key wouldn't open them.
Fortunately the rear hatch would open so had to remove parcel shelf, clamber in (not easy) and reach through to press start/stop button and kill the engine. Then opened the doors with the spare key.
Not the kind of palaver you need at 6.30am on a dark and freezing morning.
Not tried to replicate it since so don't know if it was a Mazda thing, a fault or just a low battery (changed it since).
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