PowerBook 520c/540c backlight interchangeable?

[croissantking]

I've recently acquired a 540c with a good screen, but the backlight is a bit dim.

I guess it's a long shot but does anyone know if the 520c's backlight is interchangeable?

 

[Paralel]

As far as I am aware, they all use the same TDK inverter, so they should be.

They're all the same type and size CCFL If I'm not mistaken.

 

[croissantking]

Right, brilliant.

 

[3lectr1cPPC]

I did a swap recently between a 5300c and 5300ce LCD, both Toshiba made. As far as I know, the 520c display was made by sharp. The 540c shipped with screens made by either sharp OR Toshiba, so you may have trouble if the manufacturer doesn’t match. I even had trouble getting the new CCFL tube from my 5300ce display fitted on the 5300c screen, and they were near identical. Best way is to take them apart and see. And yea, they use the same inverter.

 

[croissantking]

I think both my 520c and 540c screens are sharp. So fingers crossed. I’ll have a look when I get it open for the recap.

 

[croissantking]

The CCFL used is identical, but the cabling is slightly different in length and gauge, and the rubber end caps are a different shape. As the terminals of the bulb are soldered, I got out my iron and swapped over the cabling.

The results aren’t that much better in the 540c though and there seems to be a dark patch towards the top middle of the screen now. Not sure if that’s a characteristic of the display or if the bulb is weaker in the middle; it didn’t appear like that in the 520c.

Would like to put in a brand new CCFL down the road, have others done this?

 

[jmacz]

I've got a broken CCFL tube for a 540c. I took the measurements of both the working one (from a Sharp LCD), another working one (from a Toshiba LCD), and my busted one (from a Hosiden LCD), and they all seem to be the same size. 3mm diameter and 218mm length (for just the tube -- not including the rubber end caps).

Looking specifically in the US, I see this company Plazmo CCFL Warehouse selling something close which is 3mm x 220mm length. The extra 2mm should be fine.

LCD Backlight Bulbs- 3mm Diameter | eBay

Find many great new & used options and get the best deals for LCD Backlight Bulbs- 3mm Diameter at the best online prices at eBay! Free shipping for many products!

www.ebay.com

And the same vendor also is listing the plug which seems to be the one that Apple is using. It's a JST 3 pin connector (only uses 2 of the 3 pins). They have it listed here:

Backlight and Monitor Repair 3 PIN JST Wire Harnesses | eBay

Why replace the entire LCD screen when you can repair it for a fraction of the cost?. Use Plazmo's high quality repair components to fix your dark or dim LCD screen. PICK UP OPTION. Buy now and save!

www.ebay.com

Thoughts @croissantking @3lectr1cPPC. I think it should work? I can probably model end caps for it and 3D print them in TPU. About $17 USD for the tube and $4 for the connector. Connector is kinda expensive but can't complain if I'm only going to buy 1. For $21 plus $7 shipping, might be worth trying to see if it works?

 

[3lectr1cPPC]

Looks good to me. I've done a handful of CCFL swaps but I haven't ordered any new ones yet. Don't see why that wouldn't work though.

 

[croissantking]

Seems fine, or you could do a LED conversion?

 

[jmacz]

Seems fine, or you could do a LED conversion?

Decided against it as I didn't want to shove another board in there right now. Considered designing a new inverter board altogether with only LED support (CFFL bits removed) but would require me to spend some time to learn more first (future exercise).

I have two of the tubes on the way. Let's see how they do.