heinrich

Any chance you could share the spreadsheet off Live please? Who knows how persistent Live will be.

Vilhuer

One local '90 S4 has that 8 pin chip fried and it can no longer hold up km data when battery voltage is off.. Either due to age limit of the chip or some other problem. In any case it always starts from 7 km when battery is reconnected.

Can anyone copy needed software into new chip? It seems this is going to be needed more widely in the future as those original chips start to fail. Easiest solution would be to make 0 km chips and allow people program them before 200km limit is reached.

docmirror

The short answer is yes. EEPROM stands for Electronically Erasable Programmable Read Only Memory. So, you get an interface like this; http://www.kanda.com/products/Asix/PRESTO-M.html or the one that the OP mentioned, you plug in your EEPROM to it, and copy the contents, then put the new chip into the interface and write it to the new chip.

Note that you need an interface type that supports chip ID 93.

Vilhuer

Burner is easy part of the problem. Where do we get binary what to write in to the chip? Are there different versions for ROW and US version, km's vs miles, C vs F, different MY etc? What exactly is stored in that memory besides how much car has been driven? Can it affect from example mpg or km/l calculation? Immediate problem is that current chip in S4 is toast and data file is needed what can be burned into ROM but it would be great if for example larger injectors could be programmed in so that fuel consumption calculation would work correctly.

docmirror

OK, well you need to have a good copy to start with, clearly. Use the dump command to receive the ASCII file from the good unit, then you can use the xml file from the OP to find the location of what you want to change. However, you need to be able to do some coding to edit what's in there. I haven't done any PROM editing for decades, so I don't know the various code statements to use.

Edit, I just checked the link from the OP and it's no longer valid, so,,, that's gonna be a problem. Sorry

Hilton

Wow its 3 years since I posted in this thread already?

Borland's post indicates Theo has taken dumps from a '90 too, so probably has the ability to burn replacement chips.

I've got a couple of eprom burners and some blank 93C46 eeprom chips - having a play with this is on my long to-do list, but its low priority so it keeps getting bumped by other stuff. I haven't desoldered the chip from the 90 GT cluster I acquired to install a socket yet, or tried to read the chip in-circuit on the 90 cluster (I want to take a verifiably good backup before desoldering the chip - just in case!). On my 90 cluster, I think I need to replace the wires between the two circuit boards - the plastic has delaminated and the strips of metal are exposed. I should at least order some ribbon cable so I have the option of making the repair, and maybe have a peek in the cluster of my '89.

If you can't find a local source, I could probably work on getting an image of the 1990 binary in the next week or two from my spare cluster and testing a zero'd chip in my '89. A local with a '90 S4 tested the 90GT cluster in his car and it worked just fine (he was diagnosing an issue with his trip computer), including plugging in Theo's tool and using the dash diagnostics.

Have you tested the capacitors? There's 4 electrolytic caps on the inner board.

Hilton

On the fuel consumption calculation:

I suspect that is controlled by the chip with the dash firmware - which is a 27C256 chip on the main board. Unfortunately not socketed like the ECU's use - but if I ever get this GT cluster working correctly, I might have a go at removing the firmware chip from my '89 S4 cluster to see if I can dump the firmware (it has K18 from memory, the 90 cluster has K25).

Sadly, I doubt we'll get any progress on changing that fuel calculation unless (Por)Ken buys himself an '89 GT to play with

Vilhuer

That main board chip simply needs to be hacked so that new features can be added like boost pressure, gearbox oil temp etc.

IBR PORSATEK

Hi,
I have a big problem, i tried to reset the odometer and the eeprom has died.

Someone have original file?

The car is 928 s4 89

The main board ref is 92864199100

New to the forum and asking for help.



Thanks for your attention.

Sorry for my english.

escargot08

Hello everyone,

Is anybody able to share me the file shared some years in the first message of this thread ? I need to put the right mileage to a cluster...showing only 5km...
I have all what is required in that topic, I have read 93CS46 eeprom, I just need to know the algorythm to correct the mileage, to increase it.

Thanks

Hilton

Hi, your mileage is lower than 256, so you can just follow the factory reset procedure.

pages 90-59 onwards has instructions and then a worked example.

PC-85-928S

Is there anyone currently in the US, that has experience increasing the mileage on an 89 S4 cluster?
Programming the EEPROM, perhaps without removal.

dr bob

I've sort of kept an eye on this thread. I wonder if plugging a blank e-prom into the socket would give us a raw start at 00 miles, so we could use the factory method of setting the miles? There have been reports here that clusters stored more than a decade had lost their stored miles and reverted to zero. Since e-proms are not selective about which addresses to forget, I'd be inclined to try a new blank chip, solder it in and see if it takes the WSM setting commands.

Were it this easy, I'm sure that shady car resellers would be onto this already. It's certainly cheap enough to try. It may get to a point where we need to look for resoldering clues as part of a PPI.

PC-85-928S

for reference

PC-85-928S

Bench power procedure