Remap / ecu question

[Norte23]

Can anyone tell me why some cars have to have the ecu taken out to remap it?
What is done when it's taken out that can't be done with it in the car?
Had a few quotes from various places & one place said £300 & another said £430 because the ecu has to be taken out to do it.

Mark

 

[Steveml63]

Hi,
ECU is taken out, opened up and then the remapper attaches small probes to the relevant pins on the surface mounted processor chip - or sometimes removes chip - then squirts new program into the processor.
This can't be done with ECU in situ.
The car manufacturers - via their ECU suppliers, are insisting on higher encryption security on the fuel injection system to prevent tampering and remapping - so the remappers have needed to become smarter to overcome these security measures!
Cheers
Steve

 

[Norte23]

Thanks pal

Mark

 

[Brunty88]

How does the handheld tuning programmer work then ?
Isn't that supposed to be plug and play?

 

[Ginger55k]

Mine was removed (sl600) as it was easier to read and copy the original file without the possibility of any voltage spikes during the copy phase, the new map was then uploaded in situ as normal through the OBD port to the ECU, again the risk is that if there was a voltage spike it could corrupt the write process, not a problem if you have an exact copy of the original.

Mine has an older ECU with a dual chip to read and write from, not sure if that makes any difference though, the mapper if he had problems with the new map could then remove the ECU from the car open up the module to write directly through the pins.

However have also done it the other way read and write on the 55 using the OBD port with a Eurocharged map direct from a PC.

My experience however has been with older cars with less security built in to the ECU to stop tampering.

 

[StephenSJason]

How does the handheld tuning programmer work then ?
Isn't that supposed to be plug and play?

It depends on the ECU. Manufacturers seemed to start rolling this encryption out around 2011 in first models of new-gen cars, until all models were refreshed. Take BMW for example, I think F-Series 5 Series cars were the first, then gradually all models were refreshed and included this new level of security.

I'm not sure if MB is now doing this, I think perhaps so if using A45 as an example but although the W204 C63 and other MB/AMG cars of that same era were of course made past this point, don't forget that their engines and management systems had been in service a while already. The W204 C63 and M156 had been going since around 2007 I think, so it wouldn't make financial sense for MB to develop and encrypt ECU's of the 507 edition for example.

ALL W204 C63's are programmable via the OBD port and a handheld unit.

I expect that the W205 will be encrypted and will need the ECU removing to tune it. The issue I see with this is that it will be, in the case of warranty, hugely obvious that it has been tweaked both by checking the system and upon physical inspection. I fully expect there to be some flag raised in STAR if it is tuned, if MB are to go the way of Audi which I hear are ruthless at finding this stuff.
I am not sure how hard it is to remove the ECU, remove/reattach the "chip" or whatever is done but I personally wouldn't be comfortable with removing the brain of the car a couple of times a year and messing with it so much in this way. It's a recipe for disaster so if you're going to tune it, you have to live with this huge risk that you're on your own.

I'm happy to be schooled though, and I am sure in time that tuners will develop a simpler way to tune these new cars.

I am not sure why the manufactures feel that they need to do this. To protect the faster/more expensive cars in their fleet from being upset by their lower models? To protect them from warranty claims that they feel they shouldn't be liable for? I'm not sure.

 

[Lee C63]

If removing the ECU or having it mapped and the dealer being able to interrogate it is a worry, there is always the option to buy another ECU. Then you just Map the new ECU and it can be swapped back and forwards for servicing etc...