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Electronics => Beginners => Topic started by: mossrom on August 08, 2023, 02:29:54 am

Title: Car Radio EEPROM Identification
Post by: mossrom on August 08, 2023, 02:29:54 am
I am trying to identify the EEPROM where the VIN is stored on a stock oem radio (Delco 09389324) from a 2000 Buick LeSabre. In similar radios, the VIN is typically stored on an 8-pin EEPROM which reads as 24C04, 24C08, or 24C16.

There seem to be 3 8-pin chips on the board. This first one looks to be an EEPROM that should read 93C46. I switched this chip from the original radio to the new one and it still shows 'LOC' on the display, and I don't think the VIN is stored there.

This second one looks like a Fairchild Si4467DY, according to another thread.

The third one I'm not sure about.

Edit: My assumption about the first chip came from this database (http://codedradio.info/?i=bn&st=6263665), and this site (https://repairalltv.com/eeprom-masca-eprom-eeprom/), but may have been incorrect.

My guess about the second chip came from this thread (https://www.eevblog.com/forum/chat/which-is-the-eeprom/msg3498132/#msg3498132).
Title: Re: Car Radio EEPROM Identification
Post by: u666sa on August 08, 2023, 04:24:15 am
That first AMI chip looks promising -- https://www.automotiveforums.com/t899623-bypassed_theftlock_on_gm_chevy_class_ii_mp3_cd_hu.html (https://www.automotiveforums.com/t899623-bypassed_theftlock_on_gm_chevy_class_ii_mp3_cd_hu.html)
Title: Re: Car Radio EEPROM Identification
Post by: Shonky on August 08, 2023, 04:56:11 am
Based on the pin connections, the AMI chip is highly unlikely to be a 24Cxx or 93C46 type EEPROM.

24Cxx
Pin 8 which would be VCC has a heavy track that runs away from it with no obvious bypass.
Caps on pins 7 and 6.
Pins 1,2,3 would be address selection for a 24Cxx but they run off elsewhere.

93C46
If it was a 93C46 why would there be test points and caps on pins 6 and 7 which are no connect.

Similarly I don't think either of the other devices are typical memory devices.
Title: Re: Car Radio EEPROM Identification
Post by: AndyBeez on August 08, 2023, 08:31:21 am
My 50 cents. Is that an I2C eeprom?
Title: Re: Car Radio EEPROM Identification
Post by: Shonky on August 08, 2023, 09:46:12 am
My 50 cents. Is that an I2C eeprom?
That is what OP is looking for however the board layouts appear to indicate otherwise.
Title: Re: Car Radio EEPROM Identification
Post by: MrAl on August 08, 2023, 11:24:01 am
(Attachment Link) I am trying to identify the EEPROM where the VIN is stored on a stock oem radio (Delco 09389324) from a 2000 Buick LeSabre. In similar radios, the VIN is typically stored on an 8-pin EEPROM which reads as 24C04, 24C08, or 24C16.

There seem to be 3 8-pin chips on the board. This first one looks to be an EEPROM that should read 93C46. I switched this chip from the original radio to the new one and it still shows 'LOC' on the display, and I don't think the VIN is stored there.

This second one looks like a Fairchild Si4467DY, according to another thread.

The third one I'm not sure about.

Hi,

Ok, whose radio did you steal?  ha ha.

Just wondering what you will do once you do find the right part number.
Title: Re: Car Radio EEPROM Identification
Post by: Jeff eelcr on August 08, 2023, 11:36:54 pm
Some early delco LOC radios had a 6 digit code, accessed in two operations then this code was looked up in delco's system.
Jeff
Title: Re: Car Radio EEPROM Identification
Post by: MrAl on August 09, 2023, 09:41:32 am
Hi,

Yes Buick has a system like that where you can get a code from the radio, then look it up online and get the restoring code for that radio.  Not sure what the issue in this thread is though if it is that the radio just needs the security code or a whole new part.