Hi all, I have chance 2 buy an X plate uk turbo with no keys and wondered if the immobiliser/transponder is built into the ecu or not if so would it be possible to use a jap ecu to bypass the transponder completely and just fit a new lock set??? Or would it be a case of buying new locks with a blank transponder key and a trip to tha dealer for reprogramming?? Can any one help

 

the transponder fits inside the key and matches the ecu i think so as long as you get a ecu with the matching chip you should be ok.
if it's a uk car i don't think its as easy as fitting a jap ecu due to the engines being different although if you did you would need to swap the cam and crank sensor wires and move the one for the fuel pump (the imob one).
i'm no expert but i hope it points you in the right direction and maybee someone on here can give you more detail.

 

it is not built into the ecu on the 99 and 00 cars.

iirc there is still a factory immobiliser but it is not part of the ecu

Simon

 

Assuming we're talking about a late model GC8 (i.e. classic shape) car, the immobiliser is *not* built into the ECU, it's a separate unit under the dash. However...

No. Even if you made the necessary changes to the wiring loom to allow this to physically work, as soon as you got the engine running you would realise that the maps on the Japanese ECU would be totally unsuited to the UK spec engine. About the only thing that'd be reasonably close would be a 99-00 JDM WRX wagon, as at least they have a TD04, but are mapped for Japanese fuel, and I'm not sure whether the engines differ in other ways. You could fit a JDM ECU and get it remapped of course but that's extra expense.

That's probably the most practical way forward. There is no such thing as a "blank" transponder key with these cars btw, that's not the way it works. The dealer doesn't (re)program the transponder in the key, he programs the immobiliser to accept the code already in the new key(s) as "good".

If you adopt this approach you will also need to factor in the labour cost of changing the lock set. The boot one just takes a couple of minutes, but the door locks need the door card to be removed, while the security bolts on the old steering lock need to be drilled out - which usually requires the whole column to be removed.

 

I am having similar problems figuring out my my98 immobiliser problems at the moment. If we all agree that for this model year the ecu is not 'coded' then cant he just buy a matching immobiliser box and transponders from a breakers, (the transponders can still be removed from the keys I would immagine), and get a lock set... hey presto all boxes ticked and no dealer time, or doesn't it work like that?

 

Yes, theoretically, provided he could trust that the keys and transponder were matched.

It might, but the possible fly in the ointment is that the recent production Subaru keys I've seen, the transponder compartment can't be levered open like on the older ones. So, if he buys a new lock kit - with two new keys in it, while you could get the transponders out of the "scrapyard" keys, you couldn't install them in the new ones without butchering them.

 

i think those keys still have the 'drawer' like the early ones, and even if you have to slice & dice the breakers keys a bit you just tape the chip to the inside of the steering cowl and get a decent cat approved alarm immobiliser with remote start, this means you wont even need an ignition key/barrel!(assuming you drill or break the old one) but if your car gets nicked dont blame me!

edit: on reflection i think some thatcham categories dont allow remote start as you need to bypass the actual key, but you get the idea.

 

many thanx guys your help puts a light on things, as for the labour etc i'm a fully trained mechanic for 13yr and work as an AA patrol so changing locks is a doddle, its just the immobiliser thing thats stumpin me.. yes it is a gc8 classic on an X plate and UK version, what I dont want to do is buy the lock set, keys and ecu etc and it not work,, so would buying a lock set with keys from a breaker allow me to have the immobiliser reprogrammed to suit stupid transponder filth eh

 

97 and 98 the immobiliser is in the ecu and you need the dealer to recode the ecu to the key

Simon

 

Isn't the easiest method just buying a new transponder key from Subaru or is that just not possible?
Presumably all they'd need the car VIN and proof of ownership?
Seems simpler and about the same cost than stripping out all the kit from a breaker and refitting it to the car.

 

Excellent, that takes a lump out of the cost.

As was suggested earlier, if you buy a used lock set with keys, and you get the matching immobiliser from a breaker, this should plug and play without any programming needed. However, you'll need to be certain that the bits you get came from the same 99 or 2000 model year UK car - '98MY and earlier are different. Subaru specialist breakers might be different but I wonder how many of them realise that you need to keep the keys and immobiliser unit matched together.

If you buy a lock set with keys from a breaker and don't get the matching immobiliser, you will need to get the one already in the car synchronised to accept the codes in the "new" keys.

Similarly, if you buy a brand spanking new lock set (Subaru refer to them, confusingly, as "key kits"), you will still need to get the immobiliser programmed to accept the codes in the keys.

Main dealers can obviously do this, but I believe I'm correct in thinking that EcuTeK mappers can also do it (JGM, as you're reading the thread, could you confirm?), so it might be worth asking both your local Subaru dealer and a local mapper, if there is one, how much they'd charge. It only takes a couple of minutes but the situation may be complicated by the fact that you won't be able to drive the car to them, unless of course your AA van comes with a trailer?!

If I was in your shoes I'd get the price of a key kit from a friendly dealer and ask nicely how much they'd charge to sync the immobiliser afterward. If you're already paying for the hardware, you hope they won't extract the proverbial with the afters.

 

Not sure they can supply replacement keys without at least knowing the key number, and even then, the immobiliser would still need to be programmed to accept the code(s) from the transponder(s). It's the cost of that that elv seems to want to avoid - although it shouldn't, with a fair-minded dealer, cost very much at all, given the amount of time it takes.

 

They don't. The new keys look the same on the outside but what used to be the drawer now appears to be moulded into the key skeleton. You can still get the front of the compartment off (but only by breaking it), but when you do, you find the transponder still firmly wedged inside and won't budge. Trust me, I know!

 

no.. 97~98 ecutek software doesn't exist, 99~00 there is no keycode in the ecu so ecutek although can remap the ecu's there is nothing it can do for the extenal to ecu immobiliser so main dealer only..
2001 onwards can be done but ecutek dealer or main dealer

 

i think those with superior knowledge have pretty much exhausted the possibilities of this thread, the only nugget I have to add is that during my recent conversations with a subaru breakers who's service I can only describe as 'GRADE A' lol, they remove & keep ecu, immobiliser box and transponders (or keys?) together. I have seen many on e-bay like this so I guess its widely known that on particular models its necessary.

 

Well I stand corrected. I mentioned to L3YMS on another thread, that I couldn't see why Subaru would go from Key coded ECU's (97-98), back to non coded (99-00), then back to key coded (01 onwards) Seems a bit mad to me.

 

I can think of a couple of possible reasons for it, but I don't know enough about the MY97-8 ECUs to know whether the theory holds out.

The ECUs used on the 99-00 cars are, to the best of my knowledge, a lot more powerful than the earlier ones, while the crypto key system was "new" on the 99 cars. Could well be that it simply wasn't possible to combine the two, at the time, for the money Subaru wanted to pay.

 

I am not at all sure but here is my guess! I think the 97/98 ecu's have a rom chip in them containing up to 4 fixed key codes. I know audi of this era had this system and you can clone the immobiliser chip using a chip reader after desoldering it, or if you are clever clone it right off the circuitboard using clips! Then you solder the clone chip into another ecu and the codes now match the keys. That ecu rom chip can also be reprogramed (officially!) via. subaru select monitor to accept new keys which have a fixed code. So if you swap an ecu then you have to reprogram it to recognise the fixed codes of your existing keys. This fixed code system is relatively easily beaten by a clever thief... clone the key using a gambit or similar 'black box', then you have a working clone key. I believe the 99/00 immobiliser uses a crypto or rolling code. The way it works is that it actually rewrites the transponder chip every time you turn the ignition off, and can remember this for up to 4 keys at a time. This means there is no longer a rom chip containing fixed codes on the ecu so they can be readily exchanged, and its just the immobiliser unit & keys that are 'paired'. The benefit of this is that if you clone a key by the time you come to use it the code on the original keys will probably have 'rolled' so your cloned key (with an out of date code) will not be recognised. I dont know why the later models had coded ecu's again, my wild theory hasn't evolved that far yet! I really dont know if thats right its only a guess as nobody seems to want to explain the systems properly, I guess they either dont know or wont say due to security risks for owners which is understandable