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located EEprom on this board.

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I read that if I swap the eeprom chips
If swaping can happen when it might come in a socket.

I think you need to go the Gods of the internet (google), with the model number of the radio and see if they can help identify which part to move.

I see that on two of the 8-pin devices, four pins in a row are connected together. In the case of this memory chip pins A0,1,2,Vss. This is common for a I2C EEPROM and sever other types of memory.

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The 5500B may be a LDO voltage regulator, its pinout seems to matche the NCP5500B.
What is the part number of the "CPU", the 32 pin chip? That may have the EEPROM built in (internal)
 
If swaping can happen when it might come in a socket.

I think you need to go the Gods of the internet (google), with the model number of the radio and see if they can help identify which part to move.

I see that on two of the 8-pin devices, four pins in a row are connected together. In the case of this memory chip pins A0,1,2,Vss. This is common for a I2C EEPROM and sever other types of memory.

View attachment 136532
It's been a VERY long time since EEPROM's were DIL and in sockets :D - and certainly not for a security feature like this one.

There's obviously a correct way to exchange radios, but this isn't it.

Essentially this thread is "I bought a stolen radio, and the security features are stopping me using it".
 
Essentially this thread is "I bought a stolen radio, and the security features are stopping me using it".
Almost any car built in the last 20 years comes with a radio that will only fit that model of car. Radio theft isn't much of a problem any more.

A lot of car manufacturers code all electronics to the VIN of the car. This is supposedly for safety or security, but in fact it is often to prevent repair.

I cracked the plastic on the front of an HVAC controller on a car. The new controller cost me £750, about 5% of the cost of a new car, which would have been about £50 manufacturing cost and the rest profit. The manufacturers want to discourage use of second hand components to keep the profit margins high.

Sometimes the coding is more benign. Many module will store the VIN, and that can't be erased, even if the module is updated. However the VIN stored in the module in those cases is never compared with the vehicle VIN, so those module can be used on other vehicles. The storage of the VIN in the modules is there so that the original vehicle identity can be stored in multiple places, not just the central module the is told the VIN at manufacture.
 
Almost any car built in the last 20 years comes with a radio that will only fit that model of car. Radio theft isn't much of a problem any more.

Druggies still steal radios out of cars, and sell them to people just as in this thread - they don't care the radio might be useless, they just want money to buy drugs.
 
My VW car stereo security-locked every time I disconnected the battery. Anyone buy one of those from a salvage yard would have to find out how to unlock it. They certainly weren't stealing it; which is a dying crime by the way: https://www.npr.org/templates/story/story.php?storyId=101998015
I'm not saying it's not much less of an issue than it used to be, just that it's still relatively common - as druggies don't care if they make very little and cause hundreds of pounds worth of damage doing so.

If the car radio security locks every time you disconnect the battery (which is incredibly stupid anyway) then there will be simple instructions to reset it - it's up to the buyer to make sure he obtains those instructions from the seller. I know it used to be a big problem for garages, as disconnecting the battery killed the radio - and obviously the garage had no clue, and often the car owner didn't either.

One of my 'recent' cars had the radio keyed to the engine management system, but the instruction book told you how to recode a different radio to the car - it involved something silly like tapping out the password with the throttle pedal? (but you needed to know the password). Since then, on the cars I've had the radios have been more integrated to the car - and no mention of any security features.
 
If the car radio security locks every time you disconnect the battery (which is incredibly stupid anyway) then there will be simple instructions to reset it
I've got a 1997 Ford that does that (and most other vehicles of the period did it). If you lost, or the previous owner lost the card/booklet with the details to reset it, well, you either looked for a hack to overcome the problem or it cost you money at the local auto repair shop to reset it.

In new vehicles, the entertainment system, like all the different electronics, is interrogated by the main computer (or the body control module) to determine if it has been messed with and causes you much expense if it determines it doesn't like you there is something wrong.
 
I have Atmel 8-pin EEPROMs if you want to modify them. All are SOIC devices that I can send to you - I'm not into surface mount IC's, just got these from PCB recycling.
 
I read that if I swap the eeprom chips, the info stored on my old Radio will get moved to the new one and the radio is unlocked.
the other way to access the EEPROM is through the JTAG interface, which will be 5 test points grouped somewhat together near the MCU chip. you will need a schematic to identify the test points for the JTAG interface, and have a JTAG device that goes to a USB port on a PC, and software to read the EEPROM data. depending on the MCU and it's features, writing to the EEPROM might be disabled after programming at the factory.
 
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