Locating the R400 connection points

Switch the R400 OFF.

You should have downloaded the hardware Maintenance Manual already, if you have not done so,

Click on the hyperlink below to download the PDF file containing the R400 Hardware Maintenance Manual, you will need to install Adobe Acrobat Reader to view the manual, Adobe Acrobat is FREE and can be obtained here -> Adobe Downloads once you have downloaded the files, close the browser window to return to this page.

Click here for ThinkPad R400 Hardware Maintence manual

It is best to Right Click on the PDF links then Save "Target as" that way you will have a copy of the PDF file on your PC.

Once you have your HMM search the manual for "Removing and replacing a FRU" then scroll down to System Board, follow the instructions in the manual to remove all the other FRUs to gain access to and remove the System Board.

Keep individual modules and their screws separate to make it easier to re assemble it correctly

You need to access the 8 pin chip, a P24S08 eeprom which is located on the system board U77 as illustrated below.

The eeprom is a P24S08 which is equivalent to a 24RF08, so any reference in the following text to a 24RF08 applies to this eeprom

NOTE:  VCC is NOT connected, the ThinkPad supplies power to the eeprom later on we will switch on the TP to analyse the eeprom.

The photo below shows a 24RF08 EEPROM from a DIFFERENT MODEL ThinkPad with the Pomona clips attached to SCL and SDA pins.

See my page on Options for Clips and Probes including making your own probes.

Assembling your TP

You need to re-assemble your TP as you will have to have it switched ON and running to read the eeprom.

Follow the Hardware Maintenance Manual [FRU System Board], very carefully, double check screw type and size for each individual module.  Assemble the TP in the reverse order used to dismantle it.

Disclaimer

I make no warranty that any of my information is correct, or safe, or does or does not breach any warranty clause,  or anything else, it is up to you to decide if you will follow all or any of the instructions to recover the Supervisor Password from a TP. It is up to you to decide, I am not responsible for the results or for any consequential or incidental damages whatsoever.