What's the deal with FIX-30P-D6 cables?

A project log for All About Laptop Display Reuse

LVDS, eDP, connectors and controllers - let's learn it all

ArsenijsArsenijs 05/24/2021 at 12:520 Comments

I've previously mentioned that, funnily enough, single-link 30-pin CCFL-panel LVDS cables are commonly referred to as FIX-30P-D6, and dual-link cables for the same kind of panel are referred to as FIX-30P-S6. I've also mentioned that, in my experience, there's single-lane panels that don't work with dual-lane cables, with different results - from having no picture to showing rainbow colors, green-tinted screen or similar glitches. (My current theory is that some laptop panels short the unused pins for the extra LVDS lanes that the panel doesn't use, and this makes the MT6820 controller go haywire because its LVDS output pins are shorted to GND).

I'm not even mentioning the fact that single-lane cables tend to be more expensive than dual-lane cables, even though they have less wires in them.

All of that is nice to know.

However, what the fuck does this thing mean?

Why are there three VCC wires in positions 1-3, when pin 1 is GND? That's going to burn out the diodes forming 3.3V backlight power, isn't it?

Did they accidentally copy part of the FIX-30P-D8 pinout, which has three VCC pins, but in the opposite location?

As an aside - what even is this specific FIX-30P-D8 pinout, which display has a single LVDS link in the middle of connector?, a very specific set of 18.5" displays, it seems. I sure hope people don't buy this cable on accident!

But yeah, what's up with FIX-30P-D6?

I haven't bought any of these specific cables to check - I do plan to. However, a bit of eBay listing picture investigation shows that not everything is as bad:

This specific cable simply uses a red wire for a GND connection. Certainly not a controller-killing mistake, also certainly a source of confusion for people who actually look at the pictures.

This mistake isn't made with FIX-30P-S6 dual-link cables: guess they wisened up? Hopefully, that is the case.

And to sum it up, FIX-30P-D6 won't burn your controller, they're just confusing.