Stock ECU - can we replace the chip with EPROM??

[naughtika]

hey fellas, as stated above..

I was talking to one of the 'team member' here at my work who happens to have a chip/eprom copier/reader/writer?!

has anyone tried it? what's the chances of us having a success in doing this? and also is there a base fuel map that we can use to program the new eprom?

I've searched everywhere but can't find any here on ozvr4.. but i think in cvr4, it's been talked about..

mods: feel free to edit or close if an existing one already exists..

 

[Guest]

if we could/knew how, it would have been done,

 

[SiliconAngel]

Chris maybe talk to Chris Rogers (Audio_Express) or Mark (Mrk_VR4) - they should be able to give you a better idea of the validity of this.

 

[CANDEE]

Off the top of my head we cannot write to our ECU's are they are non-EPROM.

I believe the way that Blitz, Mines ETC have done it is they have inserted a new chip that is EPROM capable and writen to that, bypassing the std chip(note: cannot confirm that as have not seen the inside of these ecu's).

J

 

[Kenneth]

EEPROM (Electronically Erasable Programmable Read-Only Memory) comes in many forms.

In the past due to packaging constraints (too big) this was held on an external chip which was either soldered into the ECU directly or put in an IC socket which was soldered into the board.

This meant that you could remove the EEPROM and play with it, reading out the data contained within and then re-writing it.

Today MCUs etc are relatively cheap to make and the packaging is getting much smaller. As such there can (depending on model) be enough EEPROM on the MCU so that you don't need and external chip for anything other than the biggest storage requirements.

As such car manufacturers (and in this case Mitsubishi) don't need the external EEPROM and it ends up being on the chip.
Unfortunately this is the case for the 6a13 VR-4.

The EEPROM can still be read and written, however you are required to go through the MCU to do so. To do this you need to know the protocol details for communicating with the MCU and how to re-write its internal storage and EEPROM.

Frankly, unless you are willing to spend many many hours working it out, then no it isn't possible. Either get a piggy back, full replacement ECU or wait for someone else to do the hard work with re-flashing the ECU.

I hope that answers your question.

 

[matchtheclown]

Mines modded ECU, does this mean it could be reconfigured quite easily?

http://cgi.ebay.com.au/MINES-CHIPPE...ryZ32094QQrdZ1QQssPageNameZWD1VQQcmdZViewItem

 

[Kenneth]

Mines modded ECU, does this mean it could be reconfigured quite easily?

http://cgi.ebay.com.au/MINES-CHIPPE...ryZ32094QQrdZ1QQssPageNameZWD1VQQcmdZViewItem

Probably not. Chances are that mines use some method to lock it down so only they could re-tune it.

To be sure though, you would have to open it up and take a look to see what they have done.

 

[bradc]

It is easier to get a piggy back or a full ecu than to spend hours trying to figure it out, so I would do just that (and I did just that)

 

[naughtika]

thanks for the inputs guys.. i know that some of the guys here would like to have our ecu to be re-programmable like the ones on the evo 9 (i think)

reason i ask about it is.. i might have someone here who might be interested in getting the job done, but of course he doesn't know much about our cars.. eg. fuel maps and other stuff, but he's telling me that if he can read the current chip that we have, then it wouldn't be that hard to copy it into an EEPROM so that alteast we can make ours re-programmable..

didn't someone here say that he was able to modify the fuel maps in his ecu using evoscan? i just cant remember if who did that..


my point of view on it is.. if we can turn the stock ecu to a re-programmable units, then im pretty sure it'll be alot cheaper than a full aftermarket and not need it or even a piggyback

 

[SiliconAngel]

Yes well on some cars you can pay $100 and get a new chip to replace the one in your ECU and away you go. If this is possible for our cars then I think that would revolutionise VR4 tuning. Chris if you know someone who's interested in attempting it I say go for your life - any electronic circuit can be reverse-engineered and improved if you have the time and money to throw at it. The problem with our cars is no one with enough knowledge has ever attempted it.

 

[Guest]

I beleive that someone in Russia has actually written back to the ECU ... maybe valmes can give us some info on this. If u look at the ECUflash site they can't write back ... yet.
Until some nerd with plenty of time on their hands work it out, go the piggy.

 

[Kenneth]

Someone in Russia took the MCU off the ECU and backwards engineered it.

There is no external EEPROM in our ECUs so you cannot possibly take it out and re-write it.

The only way is to re-program the MCU or get it to re-write it's internal EEPROM.

The chips are re-programmable and that is what EcuFlash does. Unfortunately there have been some problems with writing back to the chip at this stage.

As I said, you can either wait until there is some progress on the EcuFlash front, do it yourself, or get a piggyback or standalone.

 

[Guest]

To be sure though, you would have to open it up and take a look to see what they have done.

If it's anything like the HKS PFC-F.CON that's sat in my garage, I bet they'll have scrubbed the IDs off any chips they've put in there so they can't be replicated.

 

[matchtheclown]

You should still be able to pop the chips into an E-prom reader and ID them that way.

 

[Hotwire]

From reading the openecu.org forums, I have obtained the two following ROMS from VR4 ECU's which members on there had successfully extracted the roms. When opening them in EcuEdit (available at http://www.epifansoft.com/phpBB2/index.php) It seems to have the definitions to allow the editing of the maps. The question I guess is writing it back to the ECU. When trying to open the .hex files in ECUFlash, it gives an error - is this what you are referring to Kenneth when you say that there is problems writing them back to the EEPRROM/ECU?

 

[matchtheclown]

Well if the ROMS are available and editable. The write back issue is the only problem right?

I'll get our guru to have a look at my ECU with me once I get my car and see if it's possible to make a piggy back board with an eprom on it.

I guess that could be pretty win. I wouldn't bother getting excited.

 

[Kenneth]

You should still be able to pop the chips into an E-prom reader and ID them that way.

MCUs generally have a few types of memory, EEPROM is one which is used for storing information that changes. This will be things like fuel trims etc, but not necessarily the fuel and ignition mapping.

Fuel and ignition maps aren't something that gets changed by the MCU while it is running, so it might be in ROM. The only way to write to this ROM is to re-program the MCU.

An EEPROM reader isn't going to do that, even if you could get direct access to the EEPROM addresses in the MCU.

You would need to get a specific interface board, remove the MCU from the ECU then dump the contents of the MCU.

You would then have to go through the dumped contents of the MCU and work out which bits are what (though this is probably the easiest bit), modify it and then be able to write it back to the MCU.


I have been doing a bit of my own MCU development and it is definitely not as simple as plugging it into a EEPROM reader. And the MCUs I am programming are no where near as complicated as the one used in the VR-4 ECU.

As stated earlier, if it were easy someone would have done it already.
It is not easy, and yet one person in Russia has still done it, go look it up if you are interested.

EDIT: here is the link to the bloke who did use an EEPROM reader. Take a look at what was involved though.
If like him you work in the industry and have access to the gear, you may have as much luck as he did. Might pay to get in touch with him before trying though, as it took him ages to get it working.

http://forums.openecu.org/viewtopic.php?t=394&highlight=h8

 

[Kenneth]

Oh, and I have some pictures of the ECU internals also, ill go get them.

EDIT:
Have attached a picture of the internals of a 2002 ECU

Comes from the following Club VR-4 thread: http://www.clubvr4.com/forum/showthread.php?t=24469

Pictures aren't great, camera was FUBAR. I'll update them when I get a chance though.