Couldnt really find a section for this..

[antus]

Yeah its not too easy. It is a little eeprom on the board, and if you do succeed in getting it if and can see the data, its not plan text or normal hex so you wont see it and then when you do know where it is, you need to figure out the checksums or else the dash will know its been changed and throw an error. Or use the VDO tool, but I dont know where or how to get that.

[Streetholden]

Yea, iv heard about someone doing that, i believe he was on this forum, kept put FFFFFFF up or similar.
I have found plenty of VDO tools, but non for GM or Holden. And from the looks of them, most plug into the diagnostics plug where as i was just told the diagnostics plug doesnt interface with the dash.

[antus]

I think the plug is on the edge of the dash circuit board.

[Streetholden]

The forth plug in the dash? That goes to the BCM i believe and 2 wires to the ECU. If it does go through the diagnostics plug, i may have found something last night about it.

[antus]

I dont know, i have only seen the high spec VN dash where it is a small connector with only a couple of pins in the center bottom. Im assuming later vdo is similar.

[Streetholden]

This is the level 3 LCD unit. As pictured. The "4th plug" is the one on the bottom, not the ones on the back. This is a 20pin plug. 18 wires go to the BCM/dash harnes and 2 go to the PCM.

[The1]

i have resoldered over a new LCD Controler board before because one of the chips died and a whole lcd wouldn't work, so the info would be stored on the vdo chip in the top of that picture.

[Streetholden]

Yea i think it would be, no other decent sized chips. How ever i found this. No idea what it is or what it does. Maybe maybe you guys might?

[antus]

That connector looks about right. Whats the numbers on the 3 smallest chips across the top?

[GM Tech]

I used to have access to this tool and it plugs into the cluster. It had 3 pins on it and once plugged in, used to display the klms from the cluster onto the unit. It had three buttons and you could select which digit you wanted to change and then use the other two for and up and down function, takes seconds to do.