Coolant leak and key fob that won't code

Monkeymad

Member
Hi I have an a2 1.4 tdi which is losing coolant , producing vapour from heater on occasion.
I also have a problem where I can't seem to code the key fob to car no matter what key fob I use.
Any help on these issues would be much appreciated
 
Hi I have an a2 1.4 tdi which is losing coolant , producing vapour from heater on occasion.
I also have a problem where I can't seem to code the key fob to car no matter what key fob I use.
Any help on these issues would be much appreciated


Do you mean a new /used key, or one of the original keys?

What process are you trying? VCDS?

Steve B
 
The key fob on the only key I got with the car doesn't work despite new battery and I have tried a few different reprogramming methods but only using key fob.
I was looking into a vcds but didn't know which one to get as I saw a few different ones available
Thanks
Keith
 
If the key has ever worked on that car then try the following.

Just put the key in the ignition and turn it on.

Then press the unlock button on it while the ignition is still on.

If the battery is ok and if the fob has worked before on that car then this will work, unless the key fob has developed a problem.

Steve B
 
I have noticed it uses a lot less water if I have the climate control off if that helps to diagnose the fault, will check the key in the morning using your notes but it does sound similar with another method I used
 
I have noticed it uses a lot less water if I have the climate control off if that helps to diagnose the fault, will check the key in the morning using your notes but it does sound similar with another method I used
There are a few "weak spots" that can cause leaks, one is the plastic piping to the rear of the engine block.

Get the engine up to temperture, switch it off and have a look with a torch for drips, they are not easy to spot but it could be something simple.

The ideal way is to remove that engine tray under the car , get the car up in the air (on a ramp, please don't take chances under a car on jacks). You should be able to spot it.

Steve B
 
Although if you are getting vapour (steam?) from the heater vents, then your heater matrix is a prime candidate.

Steve B
 
As luck would have it my dad has a car lift so will ask him about using it. I have looked into a new heater matrix or Heat exchanger and I am having a bit of trouble sourcing one that I know will fit
Thanks
Keith
 
Hi Keith,

Are you able to spot a part number anywhere on your key? You may have to split the key into it's two halves. You should see either 8Z0 837 231 or 8Z0 837 231 D.

Although if you are getting vapour (steam?) from the heater vents, then your heater matrix is a prime candidate.

I agree with Steve, the heater matrix does look likely. It may be worth checking at low levels in the front of the car to see if water is collecting in the footwell voids or somewhere similar. The ECU and other electronics are in the passenger footwell, so you'll need to keep these as dry as possible.

Matt.
 
My key has 8z0 837 231 On it

Is there an easy way to change the heater matrix or is it a day and a half job to change. If anybody on here changes them and is willing to change it cheapish I wouldn't mind bringing the car to them

Hi Keith,

Are you able to spot a part number anywhere on your key? You may have to split the key into it's two halves. You should see either 8Z0 837 231 or 8Z0 837 231 D.



I agree with Steve, the heater matrix does look likely. It may be worth checking at low levels in the front of the car to see if water is collecting in the footwell voids or somewhere similar. The ECU and other electronics are in the passenger footwell, so you'll need to keep these as dry as possible.

Matt.
 
My key has 8z0 837 231 On it

Hi Keith,

Okay, that's good. Given that you've listed your car as having a registration year of 2001, it should have a 'Q' CCCU. If you could confirm the part number of the black box on the top when you look under the passenger footwell carpet ends with a 'Q', then all will be well. Your key and CCCU will match if ending in Q, so the problem lies in either the fob functionality or coding to the car.

Matt.
 
I would contact Tony at "A2 cars", Milton keynes - 01908 824400, and ask him for a quote. He has a wealth of technical knowledge and will be fair and honest with a price !. Roughly an hours travelling distance for you too.

Ta
Dave
:)
 
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I've had the chance to get the a2 on a ramp today and still can't work out where the coolant leak is coming from but did work out that it seemed to be coming from around 6 inches above the temperature sensor, which I also replaced. Could it be the water pump? It doesn't seem to be the heater matrix and Am not sure where else to look without taking a lot of the car to bits. Any help or info would be good
Thanks
Keith
 
Update, think leak is fixed

I've had the chance to get the a2 on a ramp today and still can't work out where the coolant leak is coming from but did work out that it seemed to be coming from around 6 inches above the temperature sensor, which I also replaced. Could it be the water pump? It doesn't seem to be the heater matrix and Am not sure where else to look without taking a lot of the car to bits. Any help or info would be good
Thanks
Keith

UPDATE

I had the chance to take my a2 to bits today to find my coolant leak and I found part of my coolant flange had broke off and lodged in the top of one of the radiator hoses and half of its rubber seal had come away and gone down the pipe. It took an hour of Google searching, £10, 2 hours collecting parts and about 5 hours taking parts off car and fitting replacements
I also found a hole in a hose connected to the radiator although I think I caused the hole by taking the hose clips off.
So far so good no leaks after a quick drive although I have an oil sensor to repair as I ripped the cable off it when fixing coolant leak and what I think could be a possible CCU fault then hopefully I will have a good working a2 to drive.
Any help or knowledge on CCU's from other members would be much appreciated
Keith
 
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