NefMoto

2001 Volkswagen Cabrio. Tried to program 2 different transponder without success so looking to do immo off so I can get this car moving asap. Thanks in advance!

Get your 24C02 eeprom memory content and then we can help with immo off :)
... or buy one of this cheap immo emulators

I was wondering if I could edit it myself. I’ll get the file uploaded, I’m busy right now. Thanks for your help

of course you can edit the eeprom yourself but you don't have to, because we'll do it for you if you want
but you have to give me all the offset 00 entry
so that I can tell you how and what to change if you want to stick to the original file
or write it in offset 00 and 60, this string 12 68 30 12 15 13 94 8C 55 AA B2 F1 50 FF 0A FA
you don't need to unpin immo but you can choose

I’m in the process of trying to read the eeprom, I read it once by accident, now I just n need to find out how to install the drivers correctly for the usb341A with ASProgrammer. I have the ECU open with my test lead on it. I can get the usb to recognize it says the eeprom not responding but I think the driver’s not install right yet. I’ve been doing so much with the drivers for VAG and Tacho cables and I have success with them, now just need to find out how to do a good setup on this usb reader

I don’t need to bootload the ecu do get the computer to read the eeprom do I? The 1st one I read was from the immobilizer unit but now I can’t get it to read. I’ve read online that some people say it needs to be desoldered, is that correct and I just got lucky with the immo box because it was easy to read

you need to desolder eeprom hot air
attention, don't overheat the eeprom
and then the reading will be correct

I did accident unsolder the wrong eeprom with a heat gun and tin foil -worked great, but I’m only going to do it if I can’t do it another way -I did successfully read the eeprom from the immo box. This is what I found out on the ECU, the eeprom is a Fairchild 24c02 (I read somewhere that’s it’s a 24c08 but I probably misread it. I got the drivers installed correctly and I figured out: good clip connection and both lights indicate -so that’s good. It’s now apparently reading the chip (it doesn’t give me the IC doesn’t respond error) but nothing populates in the field (I’m assuming I need to match the manufactures’ part number in the reader. I tried other model chips and same thing reads but doesn’t display anything. There is another eeprom chip 9025 by ST

if you want 24C02 it has to be like that, no other
i think you need to buy another programmer
it's not super good but better than what you got
https://pl.aliexpress.com/item/1615435774.html
I hope this ecu is still alive after the heat gun

CH341A based programmer is good enough for SPI and I2C EEPROMS. I use one of those myself.

I do not know this device CH341A
because I don't have it
I don't know what problem you have with the driver
take photo of good quality ecu PCB
I will try to show you which eeprom it is

I’m having problems uploading the pictures;

I think the fairchild 24c02 is the correct eeprom, the last one is the one I accidentally desoldered and my resulting poor sodering job (that’s why I prefer not to desolder unless I absolutely have to. Just to clarify, I shouldn’t have problems reading/writing without soldering? I’ve read online about problems but it appears only when trying to do it through the OBII port

I had to change the image sizes

I did install in the car after the initial soldering job and all lights acted normal and it would start and quit like normal (still immobilized) so I think the ECU is not damaged, with no significant issues observed, from the heat gun

Not trying to veer off topic but I might have found out why I can’t finish programming the key because of a 8 digit precode?). I tried to use a BMW key with the same transponder but maybe I need a volkswagen key? I used the BMW key because I already drilled out my ignition so I didn’t need the proper blade cut.

https://lockmedic.com/2018/02/08/a-long-explanation-of-why-we-dont-do-vw-audi-keys-or-how-i-learned-to-stop-worrying-and-love-the-war/

https://lockmedic.com/2018/02/08/a-long-explanation-of-why-we-dont-do-vw-audi-keys-or-how-i-learned-to-stop-worrying-and-love-the-war/

Quick response anyone? Is it absolutely necessary to desolder -and not use the test clip I have. I’m trying to figure out this problem, hopefully by today

ok now you are sure that your further work will not be wasted

you can use the clip
but remember you are using very simple equipment
something can always go wrong
and ecu it may be alive but not usable
your job your risk

You’re awesome, thanks for the confirmation

My earlier setup was tested for that eeprom so I’m still trying to figure out the problem but it helps for the confirmation

Do I need a different programmer than ASProgrammer? The other program is the chinese program designed for this usb interface but the hex field isn’t populating in either one

this ecu will not let the eeprom be empty
so you read it wron

ok just to clarify I don’t need to desolder, I just need to figure out what I’m doing wrong. I assume the eeprom is not empty so I’m doing something wrong, you are correct. I can try testing again but I’m trying to figure what I did wrong. It looks like the interface is being detected fine, without checking again I don’t think there’s an availability to change the COM port. Perhaps that’s my problem?

Someone is telling me that I might have to apply power to the ECU; If so what is the best way? I’ve read a a tutorial using MPSS over OBDII and applying 12v to pin 46 if I recall correctly. Can I do it s without following the MPSS tutorial and just bench apply 12v to pin 46?

enter +12 and provide ground
and do a reading test with the clips

I’m super new on this stuff but I think I’m able to figure out what to do, with your help appreciated. The info on this other forum claims there’s no reading over the k line so I’m guessing I’m going to have to desolder -unless I’m able to find an original file with the same HW number (I read that the SW number can be different) then I can immo off then flash using MPPS with 12v applied to pin#. At this point it doesn’t look like I’ll be able to read without desoldering so I’m going to try the in emergency start procedure and see if that works since I prefer to get the car moved asap. Thanks for your help

Just to clarify it looks like I will only be able to read by soldering

immo off is eeprom not flash
pin 1,3,43 +12 and pin ground needed to power the reading ecu with clip
this programmer will not raise the voltage
without ECU power
therefore the reading is blank
because this programmer
does not check the connections of the feet for correctness
if he checked it, he would show the error of tension on his legs
you only need four wires to read
+12, ground, SC, SD
or without power Pin 43

you’re awesome and I super appreciate you helping me with this. So I’m guessing I can directly apply 12v to the pin indicated while the test strip is on it (I assume I don’t need to apply ground as that’s probably done by the test strip. This will allow me to read it, also write when I’m ready to immo? Please confirm, thanks!

I read somewhere that automotive eeproms, commonly, the pin layouts are inverted, is that true? I might have misread that

if both devices are on common ground
you don't need anything else

it is possible, make sure it is not

ok I’ll do a little more research, thanks for the quick reply

sometimes everything I write doesn’t post:

here’s the source for the automotive inverted eeproms, true or not. Ok I’m going to take your comment as an affirmative. I’m going to go ahead and test with the 12v applied directly with the test clip. If I get my car emergency started today then it’ll be maybe tomorrow when I can actually proceed to read the eeprom dump

if the eeprom is not reversed then pin 2,3,4 are ground
and pin 8 is +12
check with pin 8 if it is +12
when ecu powered
https://pdf1.alldatasheet.com/datasheet-pdf/view/446882/TGS/24C02.html
http://www.datasheetq.com/24C02-doc-Atmel

I googled inverted eeprom pins and didn’t find anything, yet; so that might have been misinformation. I did look at the datasheet and it’s saying ~5v for the supply voltage so I’m hesitant to apply the full 12v. I also notices there’s no write protection on the 24c02 (which is mine) as opposed to the 24c03 with write protection. I was doing more reading on a different bigger chip and it was specifying 12v to write but the read pin was different as well

attached

not sure how I’d step the voltage from 12v to 5v without accidentally erasing/writing to the eeprom

eeprom always has +5 power nothing else
+12 will kill eeprom
if you power up +12 ECU, you only need SC SD AND GROUND +5 will give the ECU to the eeprom

Or maybe the extra voltage wouldn’t hurt it? I can always ‘try it out’

You replied quickly. So apply the 12v to the ECU? Is there a way to do that? I know I could hook it up MPPS style and apply the 12v but maybe that tutorial was only for flashing and not reading. hmmmmmmm

I’m glad I didn’t immediately apply the 12v directly to the eeprom. That would have been an ‘oops moment’ lol

eeprom can be deleted by itself, only below + 5v
but I don't know anything about it
give +12 on ecu as mpps says on eeprom there will be +5 pin 8

always ask if you are unsure

thanks for the clarification on that

didn’t post everything I write, again

thanks for the clarification on that

So I’m going to apply the 12v to the 3 indicated pins (maybe ground too?) and simultaneously read it from the test clip. Orrrrrrr, can I just hook up the ECU and turn the ignition on and read from the test clip? I think that’s the easiest way without having to clip power directly to the ECU

just to clarify I meant hook up the ground too not apply power to ground lol

but ground MUST BE common
but detach +5 on the clip

I read a lot of EEPROM in this way

just to make sure I’m right on this. I’ll tape off the 5v lead coming from the clip. The ground will be going through the car and it’ll be grounded at the clip too so everything is correct? I’m not at the car right now but I’m going to attempt the emergency start procedure and if unsuccessful then I’ll clip it while the ECU is plugged in and I’ll cycle the ignition to provide power then I should be able to read the eeprom, and write when I’m ready

I’m off to go start on this. First thing to find out if the emergency start procedure works on this car

Epic failure, apparently no emergency start for 3rd generation immo2. I taped off the hot wire, nothing. The chip pins were inverted I think because the number 1 pin on the chip was directly opposite (same side top wise). Both lights would not come on until I unbared the hot wire on the clip and unhooked the ECU from the car. Next step desolder? Or am I doing something obviously wrong? I’m not sure I understand fully if the grounds are common or that’s what’s causing the problem. I was really hoping I could get it running today. I’ll give it another shot tomorrow but I might have to just desolder it

I have removed the eeprom with the heat gun desolder method. I will post the dump soon today

Ran into a problem, it would only read with the chip upside down (inverted?) but only zeros populated (same as before). I then hooked up my immobilizer eeprom and it read zeros too. Is my usb reader fried or maybe I still don’t have the driver’s installed correctly? I did double check the eeprom model number and the settings seem correct

If you read anything(even zeros) that's mean that drivers are ok.
Did you put programmer adapter into proper position(there is 8x2 ziff socket, half is for i2c and second half is for spi)?
There is as well possibility that you killed it in your earlier attempts.

yeah it’s in the right half and it’s clapped down so I have both lights. I assume you meant the usb reader killed? I don’t think I could have messed up both eeproms unless having them in the car at the same time did something

https://www.microchip.com/forums/m/tm.aspx?m=53053&p=1

see below

I took a spare fairfield 24c02 and was able to read it quickly with no apparent problems. I tried the immo and cpu eeprom and neither one are detecting the chip AND now for unknown reason the spare chip isn’t reading -I wonder if it had ‘enough’ voltage along with a capacitor lying on the scrap board (broken off from original ECU). Did I get unlucky and all 3 eeproms were electrostaticly fries or is there a different reason? Apparently the eeprom reader is good. I ALSO found out when I read the spare that both on and run lights don’t need to be illuminated contrary to what I thought before. Please help me, anybody, I would like to get this programmed today if I can

see above

sorry for the confusion: I’ll write something and not everything saves

After reading about someone who stated it’s completely normal to try many times to get a good connection with the test clip. I tried many times and it finally read it

ImmoOFF file requested preferably asap so I can get my car running today, thanks in advance!

unfortunately the eeprom is misread is size 0 kb

it’s my iphone. I’ll fix it

I saved .bin if that helps -it’s 256 bytes, is that too small? I can try to read it again

0 kb
enter a binary string offset lines 00, 60
you will write the data to the eeprom file yourself
or take a picture of eeprom data

I have no idea how to enter a binary number on those two lines. Sorry I’m almost completely new on this

I’m willing to edit it myself. I read somewhere about replacing A0 with 50 or subtracting 50 to make immo off

I have a picture, I’ll post it in a minute

try to take a picture of all the binary data
I'll send you the eeprom dump file with immo off


ok

hopefully that covers everything, I think I didn’t move the picture to the left. Let me know if v I need to change it, also inform if it is indeed a complete read or not, thanks

immo off

awesome thanks