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Discussion Starter · #1 ·
Hi,
I usually lock and unlock the car using the key fob buttons but it's stopped working. I swapped to my spare key, which didn't work either. I had to open the door using the key manually, which set the alarm off. Put the key in the ignition and the alarm stopped. I can start the car fine but just can't lock/alarm with either fob. I also replaced the battery in one fob just to check but it made no difference. Any idea what would cause this?

Thanks.
 

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Disconnect your vehicle's battery. Clean all battery connections and accessory connections that connect there. Re-attach and try again. You must always eliminate this variable first before moving onto additional troubleshooting.

All advice following this is under the assumption the above-mentioned variable was eliminated.

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Are you certain that the “new” battery that you put into the fob was good?
Sometimes these things sit around forever. A quick voltage check might be in order.

I like Philster’s idea. Lets eliminate all the easy possibilities before going deeper into the problem.

Good luck!
 

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Discussion Starter · #5 ·
A few months on from this and I checked the battery, the fuses, changed the battery in the fob. Rebooted the car by unclipping the quick release terminal. The central locking works if you use the button inside the cabin. All other electrics work fine.

In the end I gave up and took it to the Alfa garage, who found no faults in the system. They changed the batteries in the fobs (again) and magically it started working. The theory was my batteries must have been duds.

However, a few weeks later and it's stopped working again! So not sure what to do now.
 

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Not sure if a diagnostic tool would show this, but there might be an error "Wireless Control Module" to be found.

This is a part in the car that talks to the key. If it has a bad connection/earth/ground, it might drive you mad.

However, I would like to know if you use your car regularly, the year, miles/kms, and where it is stored.

Just feels like a problem on a car that is seldom used (if this is not the case, then I correct all the data in my head).
 

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Do you have two keyfobs? Try the other one and see if same issue still. That would tell you if it is the keyfob or something else.
 

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Hook your key-fobs up to a Tesla - their batteries are awesome
 
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Discussion Starter · #10 ·
@Philster The Alfa report said they "checked with wiTech for DTC's relating to keys and found none" and then they said there was "zero voltage from both keys", changed fob batteries, fixed... but now it's stopped working again.

True the car hasn't been used much because there was a 'Stay At Home' order here from January-March, so the only time I was allowed to drive it was to the vaccination centre :) But it was trickle charged and started regularly to keep the engine conditioned (I know that's not ideal but it's all I could do). It's a "weekend car" so I only drive it once or twice a week.

Is there a way I can check the ground connection on the Wireless Control Module? Where about is the module?

I'll may try removing the batteries in the fobs and re-inserting them in case that's what made it work when the garage tried it.
 

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Discussion Starter · #11 ·
I have done a bit more testing and found something interesting.

I decided to change the batteries again. Replaced both fobs with brand new batteries and both fobs started working. The remote central locking works fine. Lights flash etc.

I tested the batteries I just removed with a multimeter and found they were flat at 0.05V. The new batteries read 3V as expected.

These flat batteries were the ones Alfa replaced two weeks ago. So it appears something is causing the batteries in both fobs to go flat in approximately two weeks. I don't understand how that could happen.
 

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I know that when I carry the key fob for any car in my pocket with my wallet, buttons inadvertently get pressed (I’ll sometimes lock a door while bending over to take something out of the boot, for instance). I know that this is not your specific issue as you’ve not been driving, but do check where you store the keys that there is nothing resting on or beside them that might be pressing a button.

You did not leave them in a pocket when you washed your pants, by any chance?

Would seem very odd that both fobs are defective and draining batteries excessively quickly.

I usually get at least a year or two out of mine, unless I used dime store (cheap brand) batteries or happen to hit a bad package.
 

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Discussion Starter · #13 ·
Naaa nothing like that. The key is kept safely stored away until I use it and then it's in the ignition :)
They look clean, no signs of dirt or corrosion.
I googled for the problem and found quite a number of owners from a range of different cars have similar problems but no clear answer.
 

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Put it down to gremlins. I heard a podcast about it and gremlins are actually real.
Smth about cosmic rays sometimes altering a line of code and causing a malfunction.
 

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Maybe wrap one of the keys in a few layers of aluminum foil and see if that has any effect on how long the battery lasts? One possible explanation is that something (likely the car) is communicating with the keys all the time and is draining them.
 

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You don't have a little human in the household that likes to play cars? One of my grandkids used to like to grab car keys that were left on the side and repeatedly push the buttons.

Cheers,

Alf.
 

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Maybe wrap one of the keys in a few layers of aluminum foil and see if that has any effect on how long the battery lasts? One possible explanation is that something (likely the car) is communicating with the keys all the time and is draining them.
You need to wrap aluminum foil on your head not the key if you want to aleviate the problem, don't take it off at night, sleep with it on and it will be fine.Trust me on this
 

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Try not washing them with your laundry every week. lol

(I'm out of answers, but your fobs could've come from a batch with an internal short that completes a circuit and drains them)

Maybe consider conformal coatings on the key fob interior bits. It's a spray that does not interfere with their operation bur prevents all sorts of issues, such as surges, contamination, etc. A conformal coating might stop any internal short circuits that lead to draining.

Did you ever have the fobs near metal dust, extreme magnetics, lightning, or other weird environment?
 

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I think there are 2 potential simple reasons for your problem. Either bad batteries (if you get cheap button cell batteries on eBay or Amazon, they are usually made from some generic Chinese factory with poor quality control), or when the fobs are stored away, something is pressing on one of the buttons so it is transmitting all the time when stored.
 

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Discussion Starter · #20 ·
@Philster Thanks for the help, at least we ruled out it's not some nasty issue with the alarm system itself.
I'll try a few things and see if anything improves, cleaning the contacts, keeping them far away from the car. Worst comes to worst I'll just remove the batteries during the days I'm not parking somewhere public.
There seems to be countless cases of this across all car manufacturers, however mostly ones with keyless entry, which is not the case here.
 
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