My remote door locking went briefly intermittent then stopped working completely for both keys. I have checked the battery in the key body and it's reading 3v. Does anybody know where the aerial and electronic gubbins that sends the power to the central locking is located, so I can check for loose wires and anything obvious. Central locking still works ok by turning the key in the driver's door.
Technical Remote door locking not working
- Thread starter Speedwell
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Technical Remote door locking not working
This happened to me a couple of weeks back. With the remote battery being 17 years old, I changed it, which seemed successful, for a few days.
I then found to be intermittent, working fine everywhere, except back at home.
Someone suggested it may be parked close to a 'smart home', as apparently some of the smart stuff uses frequencies close to the fob frequency. I moved the car one car length up the road, no problems since.
The fob transmits a new code each time, using an algorhythm. The car receiver sits waiting for any of the next 3-5 signals. If it does not receive a signal, such as out of range, or if the buttons have been pressed when away from the car, the fob will transmit a code further along the list. Usually pressing the button 3-4 times will allow the car to recognise the sequence as its own, and reset. Worth a try.
The car's receiver is not a known issue, so worth exploring external issues first. A vehicle locksmith should be able to check the fob is transmitting.
I then found to be intermittent, working fine everywhere, except back at home.
Someone suggested it may be parked close to a 'smart home', as apparently some of the smart stuff uses frequencies close to the fob frequency. I moved the car one car length up the road, no problems since.
The fob transmits a new code each time, using an algorhythm. The car receiver sits waiting for any of the next 3-5 signals. If it does not receive a signal, such as out of range, or if the buttons have been pressed when away from the car, the fob will transmit a code further along the list. Usually pressing the button 3-4 times will allow the car to recognise the sequence as its own, and reset. Worth a try.
The car's receiver is not a known issue, so worth exploring external issues first. A vehicle locksmith should be able to check the fob is transmitting.
Does the key work if you sit in the car
Does the LED flash when you press a key
Does the LED flash when you press a key
All internal to the body computer
The body computer also controls the lock, lights and indicator
Never known one to fail
Buttons on remote fail all the time
Broken joint at the tip of the remote is common where the board goes thin
Thank you for your replies, here is what happened when I tried them
Multiple operations had no effect.
LED flashes when button is pressed
Worked fine inside the car, also worked ok through the driver's window but very intermittent through passenger window and windscreen.
I think we can rule out smart house, as ours is not smart and next door is not occupied at present. Also didn't work in LIDL's car park.
Any conclusions from that please ?
Multiple operations had no effect.
LED flashes when button is pressed
Worked fine inside the car, also worked ok through the driver's window but very intermittent through passenger window and windscreen.
I think we can rule out smart house, as ours is not smart and next door is not occupied at present. Also didn't work in LIDL's car park.
Any conclusions from that please ?
Working only from close by suggests weak battery. Was the replacement battery fresh, and a good brand, or been sitting in a drawer for ages. (Always annoying when they come in pairs and you only need one, then the other is no good when eventually needed.)
Battery connections inside the fob may just need a light clean.
A local auto locksmith may be able to test the signal strength.
That's great
The closer you are the better it works
Classic symptoms of a weak battery
You can't always tell with a volt meter, you have to measure under a load
Everything as per @portland_bill
I have struggled with home bargain batteries, bought some for my camera takes one picture and switches off same as the original. It's easy to assume it's something else, but changed for ALDI batteries and it's been working fine for months.
Fairly sure there's no seperate antenna unlike the fiat vans which runs behind the A pillar trim, if you have no joy with a different brand battery I will pull out the schematics for the body computer
The closer you are the better it works
Classic symptoms of a weak battery
You can't always tell with a volt meter, you have to measure under a load
Everything as per @portland_bill
I have struggled with home bargain batteries, bought some for my camera takes one picture and switches off same as the original. It's easy to assume it's something else, but changed for ALDI batteries and it's been working fine for months.
Fairly sure there's no seperate antenna unlike the fiat vans which runs behind the A pillar trim, if you have no joy with a different brand battery I will pull out the schematics for the body computer
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I tried a new battery, admittedly not a posh make but 3.3v and no different. It's not just a distance thing, if I aim it through the glass, it works, if I aim it at the meta , it doesn't. It seems the metal is shielding the aerial ( or whatever receives the signal). I recently had a new window actuator in the drivers door although did not immediately stop working. Could this be relevant ?
Thaks in advance for any help.
Thaks in advance for any help.
Doubt it
There's no seperate antenna shown on any circuit diagrams or component location diagrsms
If you are sure the transmit circuit has enough volts then the next place to look would be the receive circuit
Fiat 500 Remote Key Works But Has No Range ? | FIAT 500 (2007+)
Hi Guy`s This is my first post on here so hopefully it will be in the right place !! My wife`s Fiat 500 has just started having an issue with the remote key. The car is a 2012 car with minimal mileage, it`s worked fine up until last week and now only works if pressed very close to the...
www.fiatforum.com
Inside the body computer as per post 4
Just above the accelerator pedal
Coded to the car you can't just replace it
Immobiliser, key code, remote code are all controlled and stored here
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It's radio waves you don't have to point at the car
Range is normally better if you hold the key higher
Some people report better range if the key is extendeded, never tried myself
Do you have better range closing than opening
If you have access to jump leads is there an improvement jumpered to another battery
Do you have an FM/Bluetooth gadget installed to play music from your phone
Range is normally better if you hold the key higher
Some people report better range if the key is extendeded, never tried myself
Do you have better range closing than opening
If you have access to jump leads is there an improvement jumpered to another battery
Do you have an FM/Bluetooth gadget installed to play music from your phone
Thanks for that. I'll see if I can find any loose wires or corroded contacts in that area when the weather abates.
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The problem will be in the key fob circuit board. When the BCM (body computer) is damaged enough to upset the antenna, the car wont run at all.
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It sounds like your remote has a dry solder joint or a cracked track on the printed circuit.
