Swapping remote control from a donor car

[rrr]

I recently bought a very low mileage 75 1.8 in from the first owner who had lost his driving license due to his age and health problems.
After solving the usual matters with head gasket etc, I want to solve one of the last remaining issues now - I got the car with just one key (knowing that it is a serious problem but I wanted to save the car because of its incredible general condition) and one plastic (black) key. The remote control did not work. I expected replacing the batteries would cure it, but it has not. Car has to be opened/locked manually. I gave up all hope that the original owner finds the second key after two months of asking.
I have got a blank aftermarket key on eBay to get the mechanical basis for the second key. But as I have no access to anyone with T4, I came to an idea that probably the easiest way how to get things working would be using the electronic parts of the key and corresponding parts in the car from a donor car I bought 4 years ago with a hole in the engine block. Both cars are 1999 1.8 manuals, nearly same equipment.
So I would like to ask more experienced members, which parts have to be used from the donor car (which has two keys with remote control working) to get things working. Any advice is highly appreciated

[marinabrian]

You will be able to use the remote from the donor car, this will not allow it to start, however if you have the black plastic wallet key, the transpomder can be used from that to allow the car to start.

Using TOAF version 4.3 here is how it's done


The used key TOAF "How To" add used remote boards to the BCU

Open TOAF, click connect..... don't bother scanning car and click on BCU button instead.

Now click on "BCU Keys", then "Read keys" and select an unused position from the drop down menu.

Now click on Add, this opens a dialogue box prompting you to enter the six digit code from the sticker on the remote PCB.

Another dialogue box now opens prompting for a password, click ok without entering anything into this box.

The next dialogue box opens prompting you to "please synchronize your keyfob", don't click ok, instead simply close the dialogue box.

Now click on the coding tab, and choose backup, after this has saved click on restore and open the file you have just saved, which in turn writes the saved data back to the BCU.

After the data restore has been completed, press the unlock button on the new remote board until it synchronises with the car.

If you go back to BCU keys and click on read you will find your newly stored key remote is there in the position you selected

Job done

Brian

[rrr]

Thanks, I sent a PM question concerning TOAF to you.

Just to make things clear - I have to dismantle the black plastic key to use the transponder from it for a new key, based on a key fob from eBay - is there any how to dismantle the plastic key? I am not afraid of the job, years of building model kits help with cases like this, but a hint from anyone who has succeeded in this would be appreciated.

Another question - if I use the remote control parts from the donor car keys, what other parts from the donor car must be installed into my car? ECU, instrument pack ...?

[Lord of Hog]

The key just prises apart. I used a small watch-repair screwdriver but I gather a flat knife blade will do just as well. The transponder is small and well recessed into a little rectangular section so you'll probably need tweezers to get it out. Reassembly is the reverse of dismantling. Make sure everything fits nice and tight as sometimes the blade can remain a bit loose and then it pulls out and remains in the lock when you try to withdraw it.

[rrr]

The problem is that the key I need to dismantle to get the transponder is not the usual key, but the small plastic "3rd" key (without any remote control), which was supplied, as far as I know, just with the early cars.

[chicochapman]

Just to clarify, when you're using TOAF put your"good" key in the ignition
and just have the other one nearby.