lost/damaged keys...what now?

[matej]

BTW I actually wrote this as a reply to an other thread and before posting it I've found out it was already sorted out and I didn't post it there. But since I wrote such a long post that could be useful to anyone in the future I started a new thread so I didn't just waste all my time and kept the info for others. Since I experienced it on both the older MB1 car without immobilizer and the new MB6 car with immobilizer I pretty much covered all the possibilities of what can happen when you lose/damage a keys to any M car and how to fix it in the most cost effective way possible.

I was dealing with that problem two times actually. when I lost my keys to my MB1 (they were actually stolen with my backpack in a pub with the car parked in front of that pub, lol, including the registration papers in the backpack) and recently to my MB6 (which actually ended up being a false alarm since I found the keys in the end, but only after I have fixed it on the car)

In the first case with the MB1 it was easier since it had no immobilizer in the key (the immobilizer was separately installed). When I asked in Honda the first time they told me I would need to purchase the new ignition box (that would cost more than 300GBP) and all the keylocks (since they insisted they cannot be repositioned) so that was not a good option to go for. So after a few days on the phone I've found a cheap locksmith who disassembled all they key locks and repositioned them to a newly fabricated key. It cost me about 50 gbp but that was many years ago. He said ANY keylock can be repositioned, so don't trust those lazy Honda dealers if they tell you otherwise.

About 2-3 months ago I thought I lost my keys to my mb6. Since they have the immobilizer it was more complicated but still fixable without the need to purchase new ignition box or ecu. The ecu has two immobilizer codes in it (each of your two keys has one of those codes in them). I was worried that the thieves could find my keys (I though I've lost them in a local park while walking the dog) and find my car and steal it. Cause they had H badge on them and not many Hondas here where I live they would use the remote box to open the car door and than use the key to start the engine. Well I knew the keylocks can be repositioned by a skilled locksmith but I thought I would also have to change the alarm - to prevent them from getting into car with the remote box (although they would not be able to drive off because of the repositioned ignition box keylock I still didn't want them taking my radio).

The locksmith can make you a new key and clone the immobilizer code from your old key. They just disassemble your old key and inside there is a chip that contains the code. If you still have at least one key you will be able to make a new one and clone the code from the old. So even if you broke the key he would still be able to read the key pattern from any of your cars keylock. So the key pattern is not a problem. Also they can reposition the keylocks to any new pattern to fit a new key (with a new pattern). The only problem is if you lose both the keys and have no chip that could be cloned.

If you have at least one body of the original keys where the chip with immobilizer code is stored (the metal part can actually be broken/bended/twisted) they will just dismantle the key, take the chip out, read the code and clone the code into the new key. In some cases the original key can be used again (they just glue the two halfs of the key together). But that depends on how easy it is to disassemble the original key to get to the chip (ie how much they have to damage the key to get that chip out). If not they would make you a new key and copy the immobilizer code to it.

I asked at Honda and they told me that those 2 immobilizer codes cannot be changed anyhow in the ecu and there is no way to remove the other one (the one paired with the lost key) from the ecu. I thought I would disable the other one and just use two identical ones but that is not possible.

Well what I did in the end was just reposition all the 5 keylocks (ignition, 2x front doors, boot and the glove box). The key from your car has many positions (probably at least 5 or more) and at all those positions the depth of the cut defines how all the separate parts in the keylock are reading your key. The very first one (the closes to the palstic handle) was not on the deepest settings so the locksmith just milled the key a bit more to the deeper setting and I could keep my old factory Honda key with the immobilizer chip in it. He of course repositioned all the 5 keylocks on my car to fit that new key pattern. It cost me about 80guid. I had some old alarm I was using in my MB1 before I lost the keys (I put some different alarm my dad in his car before he upgraded it and kept the original one) so I was about to swap the alarm as well. The next day after I did the repositioning of my keylocks I have found the keys I though I've lost at home (although I was looking for them for few days everywhere) ;o]

So I wasted 80 quid because having a mess at home. Than I just milled the first position on the original key so it would match my repositioned keylock in my car.

So if you ever find yourself in a similar position don't trust what Honda tells you and find yourself a good locksmith and for god sake don't get yourself fooled into buying a new ecu and ignition box.

The prices of getting the old keylock out, repositioning, and getting it back in can vary hugely. In the end I've found a locksmith that did one keylock for 17quid. So I had to pay 85quid for repositioning all the 5 keylocks in my car. But when I phoned many many locksmith companies I got quoted for the same work as high as 300-500 quid for repositioning 5 keylocks. So take your time and find a cheap locksmith.

[Dave]

Good bit of info there mate