Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: Stu.C on 16 December 2022, 21:47:36

Title: ECU interchangeability
Post by: Stu.C on 16 December 2022, 21:47:36
Evening folks,


I get that you can technically run an X30XE on an ECU combo from a 2.5, but is there actually a different map in them?


Reason I'm asking is that I'm vaguely looking around for a backup ECU with the longevity of the Invisible Omega in mind. Concerns are that I've only got the one transponder chip should it ever get lost, or that the EEPROM gets forgetful in its old age. Either way, if the engine's otherwise mechanically sound, it'd be a shame to get locked out of it.


2.5 ECUs are more plentiful, it seems - so wondered if I'd be short-changing myself if I picked one up?  :y


Oh, and part B - is there anything different about an ECU for an auto, other than needing to ground out the pin for the selector lockout if using it in a manual?


Cheers, Stu
Title: Re: ECU interchangeability
Post by: zirk on 17 December 2022, 00:23:49
If we are talking about simular years, or close to bear in mind Preface and MiniFace), then it should work, as long as you've done the the ECU + Transponder Module + Key Chip, you are correct they will be different Maps but My experience of ECU Swaps is mainly on the 3.2, and again a 2.6 will work and get you out of trouble or run permently if you not that bothered about the Map difference.

You are also correct on the Auto / Manual thing with the earthing of one of the pins, but just to point out this is not the same or an easy fix for the 2.6 / 3.2's.
Title: Re: ECU interchangeability
Post by: TheBoy on 17 December 2022, 10:16:24
For a given year, the hardware is identical but the map varies.  The map is a socketed, plug in EPROM on those, so trivial to reprogram.  Can't remember chip type though, I think it was a bit smaller than the 512Mbit one used on the diesels of the era.

For non DBW V6, there are at least 2 hardware types, I seem to recall the changeoever was between MY96 and MY97, rather than PFL/MFL, but I could be mistaken on that. Best get same model year if poss.

I have the factory map from my old 1998 retail MV6, and also have a map from whatever chip mine had in.  Looks like they they are 64KB = 256Mbit if my maths is correct.
Title: Re: ECU interchangeability
Post by: zirk on 17 December 2022, 14:38:06
Can't remember chip type though, I think it was a bit smaller than the 512Mbit one used on the diesels of the era.

I have the factory map from my old 1998 retail MV6

Fairly sure they were M27C256 so yea 256mbit, which reminds me, still go some 3.0 Superchips and ExPlod Courtenay Chips kicking around somewhere, thanks TB forgot all about them.
Title: Re: ECU interchangeability
Post by: Stu.C on 17 December 2022, 19:18:24
Well that's all rather jolly news thus far  :y


My ideal target is therefore another 98-upwards 3.0 ECU with a transponder and pair of keys. I've not seen any 3.0's with a later code than 0261204589 (AF) - same as mine. If anyone's got a list handy, were there subsequent codes I could add to my search list?


3.2/2.6 ECUs weren't even considered, what with the whole DBW thing, the different coil pack arrangements and prolly a host of other things.


As an aside, if I can pick up an ECU on its own super cheap, I'll happily have a play at removing the immobiliser function altogether. I see that Ian Cass had success doing that with his MGB project - and for the sake of a few quid, it'd be an amusing/interesting nothing ventured, nothing gained kinda project  :y
Title: Re: ECU interchangeability
Post by: Stu.C on 19 December 2022, 23:08:44
Of course, if any readers do have something suitable just sat there getting dusty, please do let me know...  :y
Title: Re: ECU interchangeability
Post by: Doctor Gollum on 19 December 2022, 23:49:11
Well that's all rather jolly news thus far  :y


My ideal target is therefore another 98-upwards 3.0 ECU with a transponder and pair of keys. I've not seen any 3.0's with a later code than 0261204589 (AF) - same as mine. If anyone's got a list handy, were there subsequent codes I could add to my search list?


3.2/2.6 ECUs weren't even considered, what with the whole DBW thing, the different coil pack arrangements and prolly a host of other things.


As an aside, if I can pick up an ECU on its own super cheap, I'll happily have a play at removing the immobiliser function altogether. I see that Ian Cass had success doing that with his MGB project - and for the sake of a few quid, it'd be an amusing/interesting nothing ventured, nothing gained kinda project  :y
2.6/3.2 are irrelevant unless you wish to change the engine and gearbox looms, sensors and ignition system, throttle pedal along with the transponder and chip... Possibly rewire the dash and ABS module.  ;)
Title: Re: ECU interchangeability
Post by: TheBoy on 20 December 2022, 15:14:11
2.6/3.2 are irrelevant unless you wish to change the engine and gearbox looms, sensors and ignition system, throttle pedal along with the transponder and chip... Possibly rewire the dash and ABS module.  ;)
Its not quite that drastic on MFL, but still far too much work, given the ECUs are bombproof, and must be plentiful on scrappers.
Title: Re: ECU interchangeability
Post by: Doctor Gollum on 20 December 2022, 15:18:37
2.6/3.2 are irrelevant unless you wish to change the engine and gearbox looms, sensors and ignition system, throttle pedal along with the transponder and chip... Possibly rewire the dash and ABS module.  ;)
Its not quite that drastic on MFL, but still far too much work, given the ECUs are bombproof, and must be plentiful on scrappers.
OK, the last too may have been an egg too far, but the rest is the minimum.
Title: Re: ECU interchangeability
Post by: Stu.C on 22 December 2022, 19:02:16
3.2/2.6 ECUs weren't even considered, what with the whole DBW thing, the different coil pack arrangements and prolly a host of other things.
2.6/3.2 are irrelevant unless you wish to change the engine and gearbox looms, sensors and ignition system, throttle pedal along with the transponder and chip... Possibly rewire the dash and ABS module.  ;)


Umm, yeah, errrr - that's kinda why I said they weren't even considered...  ::)
Title: Re: ECU interchangeability
Post by: cam.in.head on 25 December 2022, 10:03:30
love the way you are realy into understanding how to systems work on an indepth level.
the info you gave me on testing my dash pcb realy helped and allowed me to sort it. still all ok and ive done your pcb you sent me as a spare. the failure mode seems to be down to the heat behind the instruments affecting the double layer board rather than a component issue. (swapped out a few first thou !)
next job on my list ,although not electrical is to make the door carches future proof. until i remove mine i havnt seen the failure mode yet but guess its either down to rust seizure or the pressed on release shaft end piece. if thats the case they will get a weld added !
merry christmas and a happy tinkering new year.
Title: Re: ECU interchangeability
Post by: Stu.C on 26 December 2022, 10:08:50
Cheers cam  :y


The tinkering will continue for sure, after a ridiculously low eBay offer got accepted on a matching ECU just before Christmas. With any luck it'll arrive by Easter ...!
Title: Re: ECU interchangeability
Post by: Doctor Gollum on 28 December 2022, 10:07:07
Cheers cam  :y


The tinkering will continue for sure, after a ridiculously low eBay offer got accepted on a matching ECU just before Christmas. With any luck it'll arrive by Easter ...!
Did it include the key chip and transponder ring?
Title: Re: ECU interchangeability
Post by: Stu.C on 28 December 2022, 17:40:51
The tinkering will continue for sure, after a ridiculously low eBay offer got accepted on a matching ECU just before Christmas. With any luck it'll arrive by Easter ...!
Did it include the key chip and transponder ring?


Nope, or it'd surely have cost more. It's cheap enough that I can poke it, prod it and hook it up to an EEPROM programmer without being overly concerned if I inadvertently kill it.  ;)
Title: Re: ECU interchangeability
Post by: Doctor Gollum on 28 December 2022, 18:39:20
Prodding and poking are additional uses to the paperweight that it is without.  ;)
Title: Re: ECU interchangeability
Post by: Stu.C on 29 December 2022, 11:02:33
Prodding and poking are additional uses to the paperweight that it is without.  ;)


Your boundless optimism and enthusiasm is infectious. Much appreciated...
Title: Re: ECU interchangeability
Post by: Doctor Gollum on 29 December 2022, 15:01:12
You're most welcome.

If you have the ability to deprogramme the immobiliser system within the ecu, without bricking it, then good luck to you :y

The Omega immobiliser is pretty simple in its components, but people almost never buy or sell the complete system and wonder why it doesn't work.

Even if you're looking to use it in another car, there's no hardship in retrofitting the transponder and wiring onto any other application. If nothing else it adds a level of security to a vehicle that might not otherwise have had any.

Just be thankful it isn't more complicated... Mercedes for example require you to change the switch unit, key, engine ecu and gear selector unit(s) as a bare minimum.
Title: Re: ECU interchangeability
Post by: dave the builder on 29 December 2022, 16:06:25
It depends on a person's skill level as to if a used ,non paired ECU is a "brick" or not ,
Eproms can be transferred or cloned  .
as can components etc from the "brick" to a failed ECU .
though it is easier to just buy a paired set and hope that 20+ year old box of tricks works  :P
Title: Re: ECU interchangeability
Post by: cam.in.head on 29 December 2022, 16:08:22
true but not as much fun !
Title: Re: ECU interchangeability
Post by: Doctor Gollum on 29 December 2022, 16:10:17
It depends on a person's skill level as to if a used ,non paired ECU is a "brick" or not ,
Eproms can be transferred or cloned  .
as can components etc from the "brick" to a failed ECU .
though it is easier to just buy a paired set and hope that 20+ year old box of tricks works  :P
If you can actually buy a matched set...
Title: Re: ECU interchangeability
Post by: Stu.C on 29 December 2022, 16:46:26
If you can actually buy a matched set...


 ::) ::) ::)


Let's go all the way back to summarising the first post for those at the back;


I'm in no rush. Hacking might work, it might not, but either way I will have learnt something. In the meantime, a Goldilocks full ECU kit might pop up for a fiver, ya never know...


 :y
Title: Re: ECU interchangeability
Post by: STEMO on 29 December 2022, 16:52:00
If you can actually buy a matched set...


 ::) ::) ::)


Let's go all the way back to summarising the first post for those at the back;


  • I've got a working ECU, immobiliser ring and single chip for my engine
  • I'd like another full kit as a backup, ideally with two transponder chips - but they're very scarce for the 3.0
  • I'd rather not go with a less rare 2.5 kit, as we've established there's a different map in it
  • I'm willing and curious enough to see if I can deal with the immobiliser EEPROM on a suitably cheap, standalone ECU
I'm in no rush. Hacking might work, it might not, but either way I will have learnt something. In the meantime, a Goldilocks full ECU kit might pop up for a fiver, ya never know...


 :y
You're better looking for a whole omega for a tenner.  ;D
Title: Re: ECU interchangeability
Post by: Doctor Gollum on 29 December 2022, 16:55:13
Are the 2.5/3.0 ecus self learning in the same way as the 2.6/3.2?

Although the 2.5/3.0 chips are readily swappable, Irmscher used to sell performance chips for them... Something that simply wasn't an option on the DBW
Title: Re: ECU interchangeability
Post by: TheBoy on 29 December 2022, 20:26:47
The immobiliser software isn't in the 29256 EEPROM, that much I do know, having regularly swapped out that chip.
Title: Re: ECU interchangeability
Post by: Stu.C on 29 December 2022, 22:50:36
Nope, it's in the B58253 - apparently...
Title: Re: ECU interchangeability
Post by: countrywoman on 30 December 2022, 11:26:20
So is there a way to remove the immobiliser from the ECU? I understood it was not possible.
Title: Re: ECU interchangeability
Post by: Stu.C on 30 December 2022, 11:33:15
Time will tell.  ;)


So for the moment, I'm not gonna sit here second guessing what will or won't happen with a spare ECU that I don't yet have, or any hacking I haven't done based on research that may or may not be finished...  :y
Title: Re: ECU interchangeability
Post by: Nick W on 30 December 2022, 11:37:16
So is there a way to remove the immobiliser from the ECU? I understood it was not possible.


It's possible to bypass the immobiliser's requirements, so the engine runs. But if you're not comfortable with removing chips, reprogramming(which isn't like an automatic software upgrade on your phone) and refitting them, it's more trouble and expense for what is a backward step, than wiring the immobiliser properly.