jmca

Just wondering if anyone with a good knowledge of different ECU's can help out. I've read a load of posts on ECU's but with no luck. My ECU looks to have one of it's chips changed.

The original chip would have been sitting in placement IC3. Instead a board containing 5 chips is plugged into the original IC3 place. Layout of the other board is...



The marking on the board CN1 is where the original chip would have been

Details of chips on the board are...

IC1 - 14pin - no marking

IC2 - 20 pin - no marking
IC3 - 20 pin - no marking

IC4 - 28 pin
IC5 - 28 pin

IC4 & IC5 have a circular window type cut-away through the black plastic in the middle of the chip. They also have the following markings on them.

These markings are as follows :



The thing is that it also alters the max boost to 1.2bar. I think normal should be 0.9bar.

Any help or information would be greatly appreciated!

Johny

jmca

Sorry the marking on the board CN1 should be the unlabelled boxed area.

Johny

StephenDone

Hi Johny,

ICs 4&5 will be EPROMs - Erasable (via UV, hence the glass window) programmable ROMs. That's as much as I can help

I think you'd better say what you car is for others to help more. I.e. year and model.

Steve

jmca

Steve,

Cheers for reminding me. I've just checked the FAQ at the SIDC site with the engine code and it shows it to be a MY95 WRX.

Johny

spender

IC1,2 and 3 are likely to be PROMs (programmable read only memory) or PALs (programmable array logic).

IC4 and 5 will be EPROMs as SD states. They are 256k sized memory chips. I think the HN means they were manufactured by Hyundai (!).

I'm not sure what the 27 means, but the C stands for CMOS, the 256 for the size and the -85 for the speed 85ns.

Every little helps.

jmca

Spender,

Every little does help. Thanks. Just wondering on the type of board. I've seen some complete ECU replacements, while some ECU mods 'intercept' the signals to the original chip - is this called piggybacking??

Could this be mine?? What is the mod that happens when the likes of superchips done?

Johny

jmca

Lads,

Thanks very much for the information & advice. I have also a UK ECU & do notice the difference when I change them. Car came with the modified one installed but with the other as an extra. I have tried to run the car since I got it on octane booster when I fill a full tank of SUL.

The difference is very noticable. It pulls like (if living) it got the fright of it's life from behind & just takes off. The Uk one is not as quick but being initially used to the other one it's not a fair comparison.

Japanese one peaks about just over 1.1, while the UK at 0.9. Mike as you say it could be anything done in Japan & as you say Alex it would be a safe decision to get it looked at from fuelling tho no trouble so far - probably due to SUL + octane booster.

Johny

EvilBevel

Long shot, but if your car is <MY98, it could possibly be the ChipTorque conversion ? I've only seen it once, but IIRC they used a board that plugged into the original ECU.

Could be wrong, mind.

jmca

Just wondering where ChipTorque are from as my from the best of my knowledge the mods were done in Japan.

Johny

Perra

Johny:

Even though I´m far from being a ECU-guru, my guess is that you have an piggy-back board mounted, possibly Unichip(???)

Check out this site for more info, if you want:

EvilBevel

I think ChipTorque was Australian ?

Mike Tuckwood

It could be anything if done in Japan, My early (93MY WRX) had a Blitz double chip on it.

The are loads in Japan.

AlexM

Hi,

From what you describe, your ECU has been remapped. This isn't a piggyback or an interceptor - In this case, the original rom map which is in the microcontroller has been replaced by external eproms. The ecu leaves the factory with the ECU program and map data stored on a rom which is in a section of the same silicon die as the microcontroller. This program cannot be altered once the chip has been 'masked'.

To allow for bugs to be corrected, and other alterations to the rom to be applied, by cutting a link on the board the microcontroller can be made to switch it's rom to an external socket. This is where your carrier board is inserted.

The reason that these new eproms are on a carrier board is that the type of eprom to fit the socket was of an unusual type (unusual word length 16 bit? and pin-out) which went out of production pretty much as soon as the car was delivered. In order to adapt the available eprom types to the socket available, a carrier board was developed to allow two eight bit eproms to substitute for the original 16 bit eprom. The other chips on the daughter board are address generation and interleaving logic to allow this to function.

Anyway, the map you have on this carrier board will have been developed for Jap 100ron fuel, and will be marginaln for safety on UK SUL.. Any further boost increases are not advisable (by superchips or other mods).

This board can be removed and the cut link re-soldered. This would allow the car to be tuned as any other MY95 WRX would be as it would be back to 'standard' tune.

As with any tuning mods (esp japanese) of unknown origin it would be a very good idea to get the fuelling checked out on a rolling road to check that all is well (even if you don't want to tune further). Power Engineering are good at this sort of thing..

Cheers,

Alex

pat

Johnny,

Please check out my reply on 22B.com, details of what it is, what it does etc on there....

Cheers,

Pat.

jmca

Pat,

Cheers for the reply. Very informative. Lucky I work in computer & have studied a little or I'd be well lost.

I'll check for the jump - LK1 over the weekend. Again cheers.

Regards

Johny