Central Locking Issue

D

DJ 190

A2OC Donor
I approached my A2 and went to unlock it. Absolutely no response from the key-fob!. I had to manually unlock the car. When I returned home, I used another fob to see if it was a battery problem. No, the car simply does not respond to locking/unlocking with either key. I have used the Forum's search engine but it is not too clear. There is some mention of possible CCU faults, but Tom (Timmus) has only recently provided myself with a replacement CCU of the latest type.
So, again, I'm seeking your help with this problem and hope for some insight as to what might be the solution? I do have another CCU that could be substituted, but let's see what is said regarding this?

David
 
I'm sure it probably isn't this - but worth asking. I dropped my key a few months back and it partially dislodged the battery. Consequently the car desynched from the key and like yours, pressing the lock / unlock fob buttons had no effect and I had to open the door manually. Firstly I had to re-seat the battery and reassemble the key. Putting the key into the ignition, putting the power on and then pressing lock / unlock / lock / unlock a handful of times was necessary to resynch it. Btw - is your battery needing to be replaced? Anyway - good luck ; I'm sure a better answer will be along soon. Edit - just seen that this has happened with multiple keys, so I'm now assuming something in the car rather than an individual key.
 
DJ 190 said:
I approached my A2 and went to unlock it. Absolutely no response from the key-fob!. I had to manually unlock the car. When I returned home, I used another fob to see if it was a battery problem. No, the car simply does not respond to locking/unlocking with either key. I have used the Forum's search engine but it is not too clear. There is some mention of possible CCU faults, but Tom (Timmus) has only recently provided myself with a replacement CCU of the latest type.
So, again, I'm seeking your help with this problem and hope for some insight as to what might be the solution? I do have another CCU that could be substituted, but let's see what is said regarding this?

David
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Hi David,
Just a thought , sometimes the key can be pressed to many times causing the keys to lose connection & may need to be resinked.

A member here “Birchall” produces a procedure in the how to section .

Put the key in ignition & press the lock unlock button on the key may be worth a try

Regards
Keith.
 
kp 115 said:
Hi David,
Just a thought , sometimes the key can be pressed to many times causing the keys to lose connection & may need to be resinked.

A member here “Birchall” produces a procedure in the how to section .

Put the key in ignition & press the lock unlock button on the key may be worth a try

Regards
Keith.
Click to expand...
To slow typing!
 
timmus said:
Start the engine. The switch the engine off, remove the key from the ignition and immediately press the unlock button.

Cheers,

Tom
Click to expand...

I read your message ..... I immediately went to the car in the garage ..... I performed the task .... SUCCESS! You are a magician, Tom! Oh, just a slight change to the procedure, though. At first, it didn't work (key still ineffective) THEN, I started the car, turned it off and,, without removing the key, I immediately pressed the unlock button. That's when it all worked fine! Another problem that this marvellous club has solved! Thank you so much, Tom!

David
 
Worth checking that nothing is frequently pressing the buttons on the remote. May also be worth checking if a button is either "sticking" or on a hair trigger thus requiring very little pressure to activate. In the past I have had other keys press the buttons causing the out of sync issue. I always keep a spare battery for the key in the ash tray and routinely replace the battery at each car service.
 
Please look back through this thread. What I outlined at the start has now become a persistent problem. Re-syncing is now very temporary .... just a journey. So is it the CCU and if I replace it, what else is involved and do I need VCDS to allow the keys to be recognised? Tom ("Timmus") has supplied both the two previous CCU's so it's a little surprising that I'm having these problems. That's IF the fault lies there?

David
 
Hi David, how old is the CAR battery, the A2 does weird things when the battery is past it. Have you checked and cleaned all connections to the CCCU under the passenger floor and it is completely dry. Can not remember if there are specific fuse(s) for the CCCU . Start with the free then work up to the most expensive to replace. Start with the car battery, check its voltage as is , check it while starting and finally check it with the engine running. After about 10 minutes running, with the meter on the battery, switch off and watch the meter readings. Take the battery off the car and fully charge it. Reconnect and repeat the tests. While the battery is on charge pull the CCCU to check its connections and look for moisture. Locate and replace any CCCU fuses. There was an app I came across a while ago that checks if the remote is giving out a signal, you could use that on your keys to see if they produce the signal only when normally pressed, or if they give off a signal all the time or by merely brushing the buttons or placing the keys differently they are giving off signals. Worth checking the remotes batteries as they could be new but nearly flat.
 
timmus said:
Have you changed the battery in the key fob?

Cheers,

Tom
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I've another key and neither would work. After doing the re-synch, all will work correctly. Then, shortly, it's back to where it was. Is it possible to check the CCCU?

audifan said:
Hi David, how old is the CAR battery, the A2 does weird things when the battery is past it. Have you checked and cleaned all connections to the CCCU under the passenger floor and it is completely dry. Can not remember if there are specific fuse(s) for the CCCU . Start with the free then work up to the most expensive to replace. Start with the car battery, check its voltage as is , check it while starting and finally check it with the engine running. After about 10 minutes running, with the meter on the battery, switch off and watch the meter readings. Take the battery off the car and fully charge it. Reconnect and repeat the tests. While the battery is on charge pull the CCCU to check its connections and look for moisture. Locate and replace any CCCU fuses. There was an app I came across a while ago that checks if the remote is giving out a signal, you could use that on your keys to see if they produce the signal only when normally pressed, or if they give off a signal all the time or by merely brushing the buttons or placing the keys differently they are giving off signals. Worth checking the remotes batteries as they could be new but nearly flat.
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The battery is new and perfect. Thanks for your help and I'll study it tomorrow. Tom and yourself have both said to replace the keys battery, so I'll do that, anyway. Thank you both for your help. This is such a good club!

David
 
My spare key was "mint", never used. However, giving it a try showed that it wouldn't work at all, even with synching. I purchased two batteries. £1.99 each, "Key Power" brand and stated to be packed in the U,K. The expiry date is Oct 2029! The cell type is CR2032. Then I happened to visit "Poundland" and guess what? I find a sheet of eight (yes, eight!) branded "Kodak" long-life and they were £1 for the sheet! (of course). Fitted a battery into the new, spare key first .... after synching, it worked perfectly! Next, my regular key. That too is now working fine! So I'm feeling good and thinking that this WAS a battery problem? There's no telling just how old those batteries were! Maybe in the key-fob from new? I'll know in a few day's if this has cured the problem.

David
 
I routinely change my remote keys batteries at each service. Also keep a spare in the ash tray. If you have a volt meter check the voltage of the old battery, although to be classed as flat the voltage has to be 2.7 volts or less. From my experience once the battery is around 2.9 volts amnesia sets in.
 
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Oh Dear! I replaced my Partner's fob battery, too. So there were three cells to examine for voltage-drop. These were the observed measurements :- 3.055 V, 3.047 V and 2.973 V. NOT what I was expecting! So I'll just have to see how this goes? Previously, after re-synching, central locking would fail rapidly, so I'll soon know if this has been successful!

David
 
You now want to check to see if any of the keys are emitting a signal when not required. That could be the plastic covers over the buttons is pressing down on the buttons, something else is pressing the buttons or a button is jammed and not returning. If you keep your keys in your pocket it is easy for them to get pressed. I did come across an app that tests Audi keys to see if there is unwanted signals but can not remember what it was called.
 
Central locking is still operational .... (and previously it wouldn't have been). So things are looking good! Incidentally, I checked the voltage of a brand-new cell. It was 3.28 V! So they are over voltage when new and the used cells that I'd tested were down .....

David
 
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My guess if the keys are not randomly sending signals is the remote system on the A2 is very picky about voltages / or read that the signals coming from the remotes. When the voltage starts to lower in the batteries the transmissions are not what the car expects and "ignores" the key, the classic out of synch. Shame the A2 remotes never had the LED to show it was working as standard, perhaps that would have shown random transmissions. I am now leaning more towards not random transmissions just signals the CCCU will not respond to.
 
My Partner has never changed the battery in her remote since she purchased her A2 in June 2003. I have never changed either battery since I purchased my A2 in 2011. I suppose that they WERE ready for replacement? I'm feeling that I will have found the problem by replacing the batteries ... Let's see and be optimistic about this ....

David
 
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