Chip Tuning Conversion: Improve Engine Performance

Hi everyone, I recently had a chip installed in my car. Now I want to put the old chips back in. The tuner soldered everything onto socket adapters, so I want to replace them myself, but the chips have two different designations: one with 'L' and one with 'H'. Now I'm not sure which one goes where.

Has anyone ever done something like this before? Or are there any schematics or layouts available somewhere?


Best regards,
Marcus

Hello Marcus,
I would also like to have the schematics and layouts.
You have 2.5 options.

1. Try it out.
If you mix up the high and low connections, the motor won't run.
(The processor in the control unit is completely lost/untraceable/offline).
Usually, nothing breaks in the process.

2. Reading out.
If you have the ability to read the chips, please do so and compare the data.
Please provide the text you would like me to translate from German to English, keeping all exactly as they are. I will only provide the translation, without any explanations.

2.5.
You are revealing more information about your car / engine code / control unit.
Perhaps someone in this forum can also tell you where things go.

Best regards, Rudi.

'Thank you, I've now found a number in the engine compartment, and I think it's the right one (D0Y). But if you say there's no risk of damage, I can just try it (50/50). Unfortunately, I don't have a way to read out the chips .'


Best regards,
Marcus


'1998 Volkswagen Golf 4 TDI, 90 horsepower.'

I hope I'm not saying something completely ridiculous right now!
Okay, so open the control unit and lay it in front of you with the connector strip facing to the left. Remove the top circuit board and flip it to the right – that's where the EEPROMs are located. You should now be able to see them clearly; one is at the top and one is at the bottom. The bottom one is the 'low' one, and the top one is the 'high' one. Insert the EEPROMs correctly, otherwise, it won't even power on when you try to start it.
Preheating lamp. You can't really break it - I've inserted it incorrectly several times on my 1Z and even used the wrong software with it.

Hello Rudi,
The description is fine for your control unit (MSA12), but it doesn't match Marcus's at all.

@Marcus:
The engine control unit (ECU) in your car is likely an MSA15-7 (which already has the split connector).
Once you've unscrewed the cover and the connector is facing you, the EPROMs are located in the upper right corner.
The left side represents the low byte, and the right side represents the high byte.

Best regards, Rudi.

Hi!

Please handle the circuit board very carefully. You have 32 different ways to insert your original chips (including rotated installation), but only one way that will make your motor start again! If you forget the order of the chips, it will take you longer for the motor to start.
Normally, the tuning chip is labeled the same way as the original, including "Hi" and "Lo." Depending on the type of chip, you'll need a chip puller (I'm not sure what that tool is actually called, sorry). With a lot of care, you can also do it without one. So, remove the tuning chip, then carefully reinsert the original EEPROMs, reassemble the engine control unit, and check if the glow plug light comes on. If it doesn't, you've either done something wrong, or the chip is faulty.
Unfortunately, reading the chip is not useful. The tuners encode their software using these socket adapters. There's a decoder built in. You can't do anything with just the chip software.

Best regards,
Uwe.

Hi,
In the 32 possibilities, you probably exaggerated .
With the storage type used, there are only 4 (or 8, if you consider the option to...).
(Installation method, including flush-mount installation, is considered).
The chips have a beveled corner. This corner must be (double connector towards the abdomen, chip's...).
(top right) is located above and to the right, while (top left) is located above and to the left.

Coding foundation:
Okay, they're preventing customers who know someone who owns an EPROM burner from...
'It's easy to copy chips. However, if you want to access the data, you can find a way.'
Often, a simple adapter with swapped address lines is sufficient.

Best regards, Rudi.

Rudi wrote:

The chips have a beveled corner.

Um, I completely forgot about that...
You are right. In fact, there are only two ways to install the chip (mounting it on top will cover the labeling)!

Rudi wrote:

Coding foundation: Okay, they're trying to prevent customers who know someone who owns an EPROM burner from simply copying the chips. However, if you really want to access the data, you can still find a way. Often, a simple adapter with swapped address lines is sufficient.

The software and hardware manufacturer claims that the sockets are individually encoded with a certain number of versions. I haven't disassembled any sockets yet, but I believe there might be some truth to that.
These sockets can be used with either the original, unprogrammed chip or the programmed tuning chip. This means there must be some kind of electronics inside, otherwise simply swapping the address lines would make the original chip unreadable.

Best regards,
Uwe

Hello Uwe,
The problem for socket manufacturers is the fact that the socket for the controller is 100% within the control unit.
It must be transparent, meaning the controller must be able to address each address as usual.
Eprom programmers typically read a chip by starting at address 0 and proceeding to the highest address.
stop. The electronics in the base (e.g., a programmable logic module or a small PIC microcontroller) detect this.
'Linear' access is then followed by swapping address lines or disabling the chip select, or whatever, to prevent...
The extracted dataset now contains only garbage.
The detection of this 'linear' access is achieved through an adapter in the EPROM programmer, where the address lines are swapped.
avoided.
This, of course, assumes that the coding base is not already soldered in place.
but is connected to this intermediate adapter.
The tens of thousands of coding options can be implemented in such a way that they are located at an address that is outside the address space of the original chip.
A code is implemented that ensures the controller in the control unit finds the correct and valid tuning data set in the appropriate location.
If the code is wrong, nothing will work.
If the original chip is installed, the base electronics cannot find its code and will execute the 'Original' version.

Best regards, Rudi.