Bigpower

Ok, so I thought I would like to do something with the Toyota ECU as I want to run the Soarer on LPG.

A quick bit of research & it appears that very few people can crack the ECU and those that have are using TomTech type mods which I think are a bit of a cludge

They also seem to want a bucket of money for the mod and don't allow any dynamic re-programming, or they all appear to be unavailable.

So................ after looking into the ECU and it's design I thought I'd try something a little different. I'm planning to replace this lot



With 1 or 2 of these




That should be fun

The coin in both pictures is a 5p piece to give some scale.

The new processors are massively more powerful than the old (what a suprise) and have acres of memory space so lots of new features are possible such as dual petrol/LPG maps, NOS control ( that might be fun), dynamic remapping and I'm sure lots of others.

I'm going to sort the PWR mode on teh gearbox while I'm at it so that it provides a decent sports change pattern for fast road / track use as the current pattern is barely different to the standard one.


wish me luck


Dwayne

just a small thought, surely putting metal things on pcb's is not a good idea?

Other than that, good luck.

Much to go wrong with it or is it fairly simple?

ValoSunnyGti wrote:just a small thought, surely putting metal things on pcb's is not a good idea?

Other than that, good luck.

Much to go wrong with it or is it fairly simple?

The Toyota ECU has a reputation for being almost uncrackable, not like your nice friendly Nissan box. Add in that it's made by Denso, who for reasons of their own, use in house chip markings but DON'T publish any data for them making stuff really hard to identify - you could say that there is a little to go wrong.

But if it was too easy - someone would have done it long ago & I'd just buy it

Metal things on a PCB is quite safe generally (as long as it's not powered on ) especially when the board is getting replaced anyway.


Dwayne

have you got a spare ECU ready

some people think I have too much spare time

This sounds like a great project, please post your results, findings, problems ad other experiences. 8)

murano3 wrote:have you got a spare ECU ready

Yes mate- the spare is on the bench right now


I wouldn't do this with my 'live' ECU as it's my daily driver.

The idea is to re-engineer the spare so it is a drop in replacement, retaining ALL of the OEM sensors, wiring, etc etc.
I'm planning to add suitable code to allow the option of wideband lambdas on the OEM harness if possible.

I think it should be fun.



Dwayne

If I read this right, you can not reprogram your ECU, so you are going to design and build your own?

You are either very clever (with too much time on your hands) or extremely brave

With the amount of time, money, and R&D, that go into aftermarket ECU's, how come you are not considering buying one? (Sub 1k) I would have thought that it would make economic sence? Or are you just after a challange?

Either way, I love people trying new idea and being inventive (God knows I have tryed to be individual with the Celica)

:thumb:

I applaud you for what you want to do, but i have to say as an ex-electronics development engineer it's no mean feat, even with schematics not only of the board but for each of the microcontrollers you're going to transplant.

You have to know what each leg of the controller does, i.e. input or output, what each of the functions are and which through hole on the board, where the controller is going to sit, is each of the legs connected to, unless you have absolutely full step by step instructions or have bought a ready to assemble/solder ECU kit.

Equally you can get converters/adapters for your controllers that fit onto where the old controllers went and you place your new controller on that, then program it but even so the adapter has to be board/controller specific. Otherwise i see a lot of soldered wires coming off each of the controllers legs to different components on the board, and that may get messy.

Personally i would just go out and buy a used aftermarket ECU for not a lot of money that will do the job equally well. However, if you are hell bent on doing this yourself i wish you best of british and may she sail forever more :thumb:

TonyB_GT4 wrote:If I read this right, you can not reprogram your ECU, so you are going to design and build your own?

You are either very clever (with too much time on your hands) or extremely brave

Maybe I'm just a little mad

TonyB_GT4 wrote:With the amount of time, money, and R&D, that go into aftermarket ECU's, how come you are not considering buying one? (Sub 1k) I would have thought that it would make economic sence? Or are you just after a challange?

To be honest there aren't any aftermarket ECUs that suit my appllication. I drive a Toyota Soarer which uses a Karmen Vortex AFM which does not present the same kind of signals you would get from a hot wire device or map system. Also the ECU controls the gearbox so a straight aftermarket device just isn't available. I specifically want to re-map both the inection and ignition system as well as altering such items as rev limiter and top speed limiter ( jap import so 180kph max). The gearbox control features 2x patterns (econ & Power) but they aren't very different. This offers me the opportunity to program a far more agressive gearbox map for the power setting suitable for track or fast road use

ScoobieWRX wrote: I applaud you for what you want to do, but i have to say as an ex-electronics development engineer it's no mean feat, even with schematics not only of the board but for each of the microcontrollers you're going to transplant.

You have to know what each leg of the controller does, i.e. input or output, what each of the functions are and which through hole on the board, where the controller is going to sit, is each of the legs connected to, unless you have absolutely full step by step instructions or have bought a ready to assemble/solder ECU kit.

Equally you can get converters/adapters for your controllers that fit onto where the old controllers went and you place your new controller on that, then program it but even so the adapter has to be board/controller specific. Otherwise i see a lot of soldered wires coming off each of the controllers legs to different components on the board, and that may get messy.

I can see wher you are going with this and perhaps I didn't make the plan very clear (I would agree that replaceing the controllers would be a nightmare). Remember that these controllers are hardly what you would call 'state of the art' more 'state of the Ark'. The particular controller I'm using has 2x main boards the one in the picture is the digital board which contains no less than 3x CPUs which I believe are 8500 based controllers - but as they are Denso marked chips, no-one is quite sure whcih variant. The other is the Analogue board which contains such things as the relevant driver circuits for Inector drive, Ignition coil drive, Baromertic equilisation, filters and interface circuits etc. This is not al that technical and can be plotted out without too much difficulty.

The conventional way of altering these ECUs (such as TomTech) is to unsolder the processor and remount it on a separate daughter board. It is not too difficult to dump out the Rom code (internal and unalterable) to an external EEPROM, and then get the chip to use the external data. The downside is that many of the original pins are used as I/O for measurement etc, which become address and data pins once set to external memeory mode. Thus you must either find a way of replacing this lost functionality or simply replace the dynamic readings with static date in the ROM chip at the appropriate memeory location.

My solution is to fully map and understand the operation of the Analogue board whcih will be retained. The Digital board will be replaced completely with a new unit, designed to interface correctly to the existing analogue board. The new digital board will run completely new code but designed to match the original functionality as closely as possible, but with the additional features I require. Given that the new processors I am using are many times faster than the originals, I'm not too concerned if my code is not as tightly integrated or as optimised as the original. Using the chips I currently have on hand gives me 16/32 bit capability with 40MIPS.

Using this method, I can incorporate any new features I want such as the different petrol & LPG maps, different gear maps and loads of realtime data logging.


If there was an easy and reliable way of doing this I'd probably take it. As it is the only available options are the likes of TomTech at about

Bearing in mind the word DENSO it's a pity you couldn't take a Scooby ECU or something similar which is DENSO manufactured and have some sort of programmable adapter interface that plugs in between the cars ECU connector and a DENSO ECU's port. Surely that would be an even easier solution to build.

I hear Scooby ECU's are even better than a lot of aftermarket ECU's, and having mapped my own i can vouch for the wide range of information available from my ECU and different parameters that can be mapped, not to mention extensive logging of practically every event in real-time.

Maybe there is some way you could re-program the controllers in whichever assmbler the firmware is written in on another DENSO ECU to get the desired effect??

Just my 10p's worth and you've probably already thought of that anyway :thumb:

P.S. Is yours a V8 Soarer or 6Cyl. I have seen an XLEM G3 system for a V8 Soarer and Apexi PowerFC that looks applicable. I'll shut up now and go to bed