T400 background CCFL not working

[mgw]

The background light died a while ago. I've replace CCFL, display cable and inverter - no change. The display works. What am I missing?

2nd question: Can some kind soul point me to a LED replacement for the CCFL?

[Neil]

Could be that there is an open fuse on the system board. Check all the fuses near the LCD ribbon cable connection.

Here is one source for retrofit LED kits: http://www.lcdparts.net/LED.aspx

[mgw]

Thanks for the hint. Where would I find the fuses?...the repair manual doesn't contain any information, unless I overlooked something. Txs again

[Neil]

Sorry, not sure about the location of the T400 fuses. I doubt that you will be able to get at the one you need to check without completely removing the system board from the chassis. Hope someone more familiar with the T400 comes along and informs us differently.

[emeraldgirl08]

Here is one source for retrofit LED kits: http://www.lcdparts.net/LED.aspx

This would be nice if it worked on the WSXGA+ screens of the T500.

[mgw]

I've replaced CCFL, inverter' display cable and system board. Still no background light. What now?

[Neil]

Did you test the replacement CCFL tube before installation to make sure it worked? And did you test it again after installation in the panel but before reassembly, to make sure it was still working? Can you connect the lid with the replaced CCFL to another T400 base, or a different lid to your base, to test it's functionality, and help isolate the problem?

[mgw]

Hmm... no 2nd T400 unfortunately. Would a T60 screen w/ CCFL work too? I.e. could I connect the T60's CCFL to the T400 inverter and vice versa or would this blow the tube or anything else? I'm unsure about the standards re voltage, frequency and alike..

Txs for your help