Hi all,

We recently purchased a MK7 fiesta as a second car for the missus, that unfortunately came with just one key from a private seller. I'm aware that's quite common, but being a bit obsessed about security, i'm thinking of replacing the locks.

I can probably source the parts from a breaker and fit them myself in hope the overall cost would be slightly higher than buying a second key (with fob) and getting it cut.

I'm just wondering if i really need to source the ECU or could do without it. I've seen some sellers giving you the speedo and ECU together with the lock barrels, but my (limited) experience tells me that shouldn't be required, unless it's something to do with the immobilizer.

I was thinking i need the following:

• Ignition barrel
• Driver's door barrel (without the mechanism)
• Delete any existing fobs and reprogram the new ones (Is this possible using ELM?)

Are those correct? Did i forget anything? Any suggestions would be greatly appreciated.

It seems an awful lot of messing around, I'd be tempted to get a 2nd key cut & programmed and buy a steering wheel lock.

Unless i need to replace the ECU (and speedo that usually goes with it) it shouldn't be a massive job and can certainly deal with it.

Won't be a 5-mins job, but certainly beats carrying an ugly steering wheel lock around.

Has anyone attempted this and can comment on the required parts? If not, i'd probably buy them and see if they fit!

You won't need to replace the ECU but you will need to program in the new key(s) given the RFID immobiliser. I have no idea how you do this - Forscan may well be able to do it.

So i managed to get hold of a set of locks and keys from a breaker and have sucessfully switched them over. They are hard to come across as most breakers prefer to sell them as a set with the ECU.

It wasn't very hard and thanks to another forum member's suggestion i only replaced the cylinders leaving the steering lock assembly and immobiliser untouched.

For now i had to keep the old immobiliser chip and will pair the second one using Forscan.

Overall it took me around 15 minutes to replace the two cylinders, and another 15 minutes to swap the immobiliser chip on one key because the old one was glued in place.

p.s. I was debating with myself in creating a guide, but it's related to car security and that's a public forum...

As interesting as any guide is I can't imagine there's much demand for this kind of modification!

3 minutes ago, MJNewton said:

As interesting as any guide is I can't imagine there's much demand for this kind of modification!

To be honest i'm surprised it's not.

The reason i desparately wanted to change them, was the fact i got the car privately with just one key and the seller has you home address from part 6 of the V5C.

Buying a second-hand car is always a risk as the seller might keep the second (or third) key on purpose. If you replace all the locks, you eliminate that possibility.

If you're super paranoid, you can send the new locks on a different address or buy them direct from the breaker so they don't have your address either :)

It might well be a risk, but the probability of it happening must surely be close to zero. This supposition is, admittedly, based on me never hearing of such a case - not least with a Fiesta! :-)

Have you always changed your locks on cars you've bought in the past?

I haven't owned that many used cars and i didn't do it on the last one i had, but it was only £500 so it wasn't worth it.

I have however been changing locks on every house i've moved to (after the appropriate notice where necessary).

Yes, fairly common on houses but it's the first time I've heard it being done on a car (for the specific reason of mitigating the risk of the previous owner stealing it). 

if the previous owner wanted to come and steal the car he sold you he could have had a third key made before he sold the car to you with two keys. So would you have changed the locks if he had given you two keys?

I am not criticising you for doing it, it's your choice. (I wouldn't have done it if they just gave me one key)

That depends on the value of the car, the likelihood of getting stolen, the cost on my premium and the difficulty of changing locks.

I've read quite a few posts about fiestas getting stolen (mainly ST tho) which means they are quite popular amongst thieves as well as customers, so I wouldn't be surprised if that's actually happening.

Don't get me wrong, I'm not trying to convince anyone to start changing locks, all I'm saying is it's much easier and cheaper than most people think and doesn't require loads of tools or skills.

The average car enthusiast can find his way round this for around £40-50 (depending on breakers prices)

Also, in the event your locks get damaged, the process is the same and saves you an expensive visit to the stealership.

I always prefer lock and ignition replacement through locksmith.

Another option would have been to have a 2nd key cut for a spare and fit an aftermarket alarm/ immobiliser 🙂

Hi we have the same issue as previously posted do you just take out the cylinder on the door which I know is easy to do, but how do you remove the cylinder on the ignition please. 
 

regards Richard