What four soldering on the bottom of the cdx m800 do u soilder together to erase the security code and can you show a pisture of what it looks like

You can enter a 4-digit security code as an option after purchase of the unit. If you do so, make sure it is noted down somewhere. If you did select a code (or the previous owner has done so) this must be used when the unit is removed from the vehicle, or the constant power source is disconnected from the unit. When constant power is restored to the unit, the security code must be entered before the unit becomes operational. If the code is lost or forgotten I am afraid the unit has to be re-coded by a Sony dealer.
Hope this helps, Good luck with it.

Radio code is specific for each and every car. It is specific like anti theft code.

You can get it by providing your VIN# and registration details in authorised dealership. Nobody else can provide you. If anybody can provide you that , then there is no meaning of security for your car..

If it is the security code you are looking for, try these solutions. See how you get on. Solutions that have been tagged as workers... try the soft fix first, then if your game,the 4 blob trick... dunno bout that one??
http://www.fixya.com/support/t225385-sony_cdx_m800_code


 I recall changing out the 8 pin eeprom chip where the security code was stored on Sony and Pioneer Head units where customers had forgotten their code when the units were brought in for service, so  you start with a fresh code. That was a few years back but:).  
Will have an 8 pin dip chip as detailed in this post if thats the case for this unit. You may need to supply your Identification toSony to order the part. This is how it used to be,and it may be doable only at a sony agent, this being a security part for the unit. Let me know howyouget on. 
regards robotek . 

pleace send pin code cdxm800 sony

HI THE FLEXI RIBBON IS FAULTY MAKE SURE YOU HAVE THE CODE AS YOU WILL NEED THIS TO MAKE THE STEREO WORK AGAIN

IF YOU DONT HAVE THE CODE THEN

LOOK ON THE BOTTOM OF THE STEREO YOU WILL SEE A SQUARE SECTION MISSING INSIDE THIS 4 BLOBS OF SOLDER JUST SOLDER THE FOUR BLOBS TOGETHER AND THIS WILL WIPE THE CODE OUT ALTOGETHER

THIS DOES HOWEVER MEAN THERE WILL BE NO SECURITY ON THE STEREO
HOPE THIS HELPS

SECURITY CODE

Underneath the unit, solder all the blobs (4 of them) and it should by pass the code. FixMyRadio dot Net

you can buy these from ebay just type in sony cdx m800 ribbon theres loads on there pretty cheap aswell hope this helps

These are the official codes from Sony, you will need the remote to enter, only one will be required by your unit:

1) DISC+ SOURCE LIST OPEN/CLOSE
2) OFF SOURCE ATT OPEN/CLOSE
3) MODE PTY/DSPL SOUND OPEN/CLOSE
4) SOUND MODE ATT OPEN/CLOSE
5) MENU ENTER MODE OPEN/CLOSE
6) SEEK- SEEK+ MODE OPEN/CLOSE
7) OFF PTY/DSPL MODE OPEN/CLOSE


Let us know how you get on

hey could sum1 please give me a securitey code for my sony cdx-800 much appraitated