"Key not detected"

banksy

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It is very rare for a car problem to be unheard of by all Maggotdrowners, so here's mine.
Hope somebody has a simple solution, but ...

My car in for MOT today, it's a 2017 Mondeo S-Line Diesel Estate.
Call from the MOT place:
"Your car's passed, but it's stuck on our ramp and it won't start.
We can't push it off, because it's an automatic and it's in Park. Display just says "Key not detected".
This happens when I've left the key fob in the house, so it is out of range. But the key was on the passenger seat now.

Thinking the fob battery might have died, I walked round with the spare keyfob.
"Key not detected".
Much wailing and gnashing of teeth. A line of other customer cars await MOT, and the ramp is blocked.

After ten minutes of trying, the car suddenly started, and was driven out of the way.
Now it starts, but oddly, the 'door open' alarm sounds when the driver's door is open, even when the ignition is not on?

So I drove round to the Ford dealers, who jumped into action, and said they'll look at for me on Thursday.
They'll run a diagnostics test, which will take about an hour and cost me £95, then they'll phone me to tell me how much
it will cost to correct the fault.
They also suggested replacing the fob battery, but I cannot believe that BOTH fob batteries failed at the same time.
In the meantime, I'm expecting the car to die on me when I'm down a little cart track, miles from anywhere, fishing.
At six in the evening.
When it's pissing down with rain.

Isn't technology wonderful?

Anyone else had this problem, and what did you do about it?
 

warrington63

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It is very rare for a car problem to be unheard of by all Maggotdrowners, so here's mine.
Hope somebody has a simple solution, but ...

My car in for MOT today, it's a 2017 Mondeo S-Line Diesel Estate.
Call from the MOT place:
"Your car's passed, but it's stuck on our ramp and it won't start.
We can't push it off, because it's an automatic and it's in Park. Display just says "Key not detected".
This happens when I've left the key fob in the house, so it is out of range. But the key was on the passenger seat now.

Thinking the fob battery might have died, I walked round with the spare keyfob.
"Key not detected".
Much wailing and gnashing of teeth. A line of other customer cars await MOT, and the ramp is blocked.

After ten minutes of trying, the car suddenly started, and was driven out of the way.
Now it starts, but oddly, the 'door open' alarm sounds when the driver's door is open, even when the ignition is not on?

So I drove round to the Ford dealers, who jumped into action, and said they'll look at for me on Thursday.
They'll run a diagnostics test, which will take about an hour and cost me £95, then they'll phone me to tell me how much
it will cost to correct the fault.
They also suggested replacing the fob battery, but I cannot believe that BOTH fob batteries failed at the same time.
In the meantime, I'm expecting the car to die on me when I'm down a little cart track, miles from anywhere, fishing.
At six in the evening.
When it's pissing down with rain.

Isn't technology wonderful?

Anyone else had this problem, and what did you do about it?
My 19 plate Honda civic diesel has a key fob warning light show on the dash when the battery is low,
Can get in the car if needed with a key that is part of the fob, ( never had to try that) but not sure about starting the car. Without looking through the 700 page glovebox handbook you get with the car.
As soon as fob light shows its a trip to the dealers for a new battery, we have 2 fobs for the car so one always has a full battery in it.
 

scuttster

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From my understanding if you get a key not detected most manufacturers now state that you should hold the fob against the starter button when pressing.
 

DFL

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My Skoda does this very occasionally. My thinking is that it's just a glitch in the software. Min resets itself when I lock and unlock the doors. In your case I'd be tempted to disconnect the battery and reboot everything before shelling out £95. Must make sure you have the radio code if you attempt this.
 

banksy

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I forgot to mention, even when the display says "Key not detected", the fob will still open and lock the car remotely!
I know this is for a ford focus but would imagine the Mondeo is similar.

That's useful to know anyway, thanks!

But I can't believe that BOTH fob batteries have died at the same instant?
And it doesn't explain the drivers door "door open" alarm going off when the ignition is not switched on?
I used a pressure washer on the car yesterday, makes me wonder ...
 

stump28

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Ahhh the joys of modern motoring gadgets.....can't believe they want 95 quid just to plug it into a computer....... and people wonder why i like to stick with cars you can fix without a laptop!!
Had a headlight replaced when the running light strip died, they charged £60 for the diagnostic even though you could confirm the light was out simply using your eyes. came off warranty anyway but ridiculous really.
 

Barbelcatcher

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Could be worse - you could be down a country lane, miles from anywhere, with the girl friend, knowing that your wife has to traverse the path in 20 minutes.

A college of mine went fishing, who lived in Lincolnshire. Locked his car, walked to the railway line - a distance of about 1 mile, caught fish. We walked back as happy as pie at he nice day we had had, loaded his car and my car with respective gear. He closed the boot lid, spent about 3 minutes talking with me - and the car automatically locked the doors, with his keys still inside the boot. His wife had to travel 30 miles to let him in. Audi from what I can remember.
 

Barbelcatcher

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Garage has rouge charged your ECU perhaps - think you have to earth it.

Perhaps as mentioned before may have run the battery down during tests
 

carphauler

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As said you can put the fob next to the immobiliser system, this was where the key would usually be to start the car on my lads car, try new batteries first, this happened to him.
 

banksy

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A little update -
I told my on about the 'door open' alarm going off when the driver's door is open.
He said:
"Have the MOT guys left your headlights on, after they had tested it?"
Doh!
Is there an 'Embarrassed' emoticon?

Still doesn't explain why two good keyfobs could not be detected while it was on the ramp.
Unless all the metal around the car was screwing up the signals?

The car is working perfectly normally now, so if it behaves itself in the next 24 hours or so, I might be cancelling the £95 diagnostics test.
 

banksy

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Thanks everybody for your replies! (y)

I tested both the key fob batteries, and they are good, but now I know where the Emergency Key Point is,
so if ever I have a dead keyfob, I'll know what to do.

But something else was messing with the key signals when it was on that MOT ramp, and it does shake my confidence in the car.
 

Dave

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My previous Hilux had an issue with the signal from the key fob being interrupted by certain door bells, believe it or not.
For some reason the radio frequency of some door bells used to interfere with it and the pickup would not open or start, depending.

It also happened to my wife's BMW X3 at the same time as mine whilst both were parked on the drive. The push button for the wireless door bell was jammed in so the radio signal from it blocked the signals from the key fob.

I bet there was something similar in the garage blocking the signal or interfering with it to the transponder in the immobiliser.

Re batteries in key fobs, if the fob is the type that allows you keyless access to a car, ie walk up to it or touch a button, or handle, the fob is constantly transmitting as it looks for the receiver regardless if near the car or not.
So the batteries can run down even if not being used and it is recommended to change both, usually as part of a service schedule, but definitely if one goes down.
 

Dave Spence

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Ahhh the joys of modern motoring gadgets.....can't believe they want 95 quid just to plug it into a computer....... and people wonder why i like to stick with cars you can fix without a laptop!!
Fair enough Al but I don’t think I’m up to cranking a starting handle on a freezing winters morning💪💪💪
 

carphauler

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My previous Hilux had an issue with the signal from the key fob being interrupted by certain door bells, believe it or not.
For some reason the radio frequency of some door bells used to interfere with it and the pickup would not open or start, depending.

It also happened to my wife's BMW X3 at the same time as mine whilst both were parked on the drive. The push button for the wireless door bell was jammed in so the radio signal from it blocked the signals from the key fob.

I bet there was something similar in the garage blocking the signal or interfering with it to the transponder in the immobiliser.
Similar thing happened to me but in reverse, my son bought his first house this year, I was down there a lot helping with plumbing, toilet install etc when a lovely old lady next door asked me if I kept locking my car on his drive. A bit of an odd question I thought, I said yes, just a habit and I didn't need to really, why? She said every time I locked it, it set her doorbell off 😂😂, i wondered why she kept appearing when I got there, I think she said she was going to switch the frequency over on it.
 

MrBen

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Most door bells and car remotes run on 433 MHz so can see how they could interfere.

I recovered a Subaru from the airport next to donnington park, that wouldn’t start, got it a couple of miles down the road, started fine, never played up again. That has a real fancy alarm/immobiliser fitted.

People leaving lights or ignitions on is a daily nightmare for me. Used to look after a few Bentley Continentals if there batteries go flat, they usually put the rear passenger windows down!
 

Dave

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My missus's car has a combination of buttons on her fob to press and it opens all the windows on her car regardless if the car is locked or unlocked.
The first time it happened the fob was in my trouser pocket and must have pressed against a few coins. All the windows suddenly dropped down :eek:
 
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