Pioneer Kuro PDP-LX5090 - Pink Tint Fix

[tom66]

Simon brought his Kuro over as he had an issue with a pink tint on bright scenes. It's had this issue since it was fixed but I guess it finally bothered him enough to get it fixed

Initially, I tried setting all panel voltages (via RS232) to the stock settings - 128 all around. Then I tried setting VSUS to code 150. This did not affect the picture. I tried lowering the ABL point, I tried increasing the VOF and VYF -- no change. Very confused, I set voltages again back to factory (always important to adjust from a known baseline)

I then tried adjusting the YSUS/XSUS resonant points YSUS_B XSUS_B. Adjusting these positively made the picture much worse, around 135 (from 128) made the whole panel pink. I then went the other way back from 128 to around 115. This made the picture perfect!

I noticed some cyan discharge errors in purple and pink colours, to fix this I increased V4F and decreased V3F. The delta between V4F and V3F has a significant effect on maldischarge. V3F also lowers the black level, but if V3F is too low other picture faults will occur.

Finally, I tested it on all types of content and the panel was declared to be fixed

[ReeceyBurger123]

Re: Pioneer Kuro PDP-LX5090 - Pink Tint Fix

Fair enough, how come that happened just age or inflicted from when you tweaked it last ?

[tom66]

Re: Pioneer Kuro PDP-LX5090 - Pink Tint Fix

To be honest I'm not sure. The panel had been tweaked by the previous owner, and many voltages were adjusted from the default settings. But after setting these voltages back to stock, I couldn't improve the image.

The only thing I can think of is that it's been adjusted before and then reset. If it is reset, it may get put out of sync with the aging algorithm which might adjust that resonant point. Or if it's had the control PCB replaced with a newer or older one.