I started an earlier thread in Harddrive forum.. but with with no response.

Symptom to troubleshoot: blank, black screen in Latitude D800.

Since posting that first thread I have eliminated some possible failed components.

(a) Latitude mains adapter and battery are working

(b) Hard disk has been removed and tested as slave disk in another PC. No data loss seen, so disk has not crashed.

(c) CD inserted into CD drive seems to work.

But since there is no display on screen (other than a few random white characters on black screen) it is very difficult to diagnose further to identify what component to repair/replace.

______________________________________________

Here is current status of testing (having now checked that HDD and power are working and can be eliminated):-

The device status lights show ..

(a) no disk read/write activity at any time
(b) battery can be seen to be charging
(c) bluetooth technology is on

I can place a CD in the internal CD caddy and it whirs as though being read.

When power is switched on there are no lights in the keyboard status lights (to the left of the power on switch).

In reading Help manual about built-in diagnostics, "if there is no display the diagnostics can be switched on by holding down Mute switch whilst pressing Power On switch".

I tred this and the three keyboard status lights were illuminated and ended with centre light on, and two outer lights flashing.

Does this "blnking light pattern" indicate any diagnostic test result?

This test did show some random white characters on the black background screen, but nothing to read. Just raster.

Anyone abe to hazard a guess as to what might be the pssible root cause(s) of display backout?

I have not been able to find any step by step diagnostic tests for "display down scenario".

One step would be to try to drive an external monitor via Fn + F8 .. but I don't have a monitor.

Message Edited by drag0nfly on 09-20-2006 05:00 PM