Sony KDL-40V3000 distorted picture

[PowerAmpFreak]

This Sony KDL-40V3000 has a distorted picture. Looks saturated.
Worst from coldstart, better when warm but not OK.
Panel or T-con should be the options here?

[PowerAmpFreak]

Re: Sony KDL-40V3000 distorted picture

Don't you think this is actually related to T-con failure?
It's possible to see the picture distortion changes as it heats up during the first 30 seconds of operation.

[Andrew F. Ali]

Re: Sony KDL-40V3000 distorted picture

I'll try a T-CON for starters.

[budm]

Re: Sony KDL-40V3000 distorted picture

Check the GAMMA Voltages on test points on the T-CON board. Did you reseat the cables already?

[PowerAmpFreak]

Re: Sony KDL-40V3000 distorted picture

Budm, what should the gamma voltages read if OK?

[Andrew F. Ali]

Re: Sony KDL-40V3000 distorted picture

GAMMA Voltages If from ! to 14 they should increase or decrease uniformly. Do as BUDM said measure the voltages and post then we can determine a fault.

[vinceroger69]

Re: Sony KDL-40V3000 distorted picture

This thread may help you by budm regarding gamma voltages post 13 shows one test results (which are bad)
https://www.badcaps.net/forum/showth...gamma+voltages

[PowerAmpFreak]

Re: Sony KDL-40V3000 distorted picture

Here's the Gamma voltages:

VGMA1: 15,44
VGMA2: 15,07
VGMA3: 14,93
VGMA4: 12,60
VGMA5: 11,61
VGMA6: 10,62
VGMA7: 6,71
VGMA8: 4,83
VGMA9: 7,66
VGMA10: 7,90
VGMA11: 7,89
VGMA12: 7,10
VGMA13: 5,30
VGMA14: 5,30
VGMA15: 5,30
VGMA16: 6,30
VGMA17: 8,51
VGMA18: 5,60
VGMA19: 3,10
VGMA20: 0,456
VGMA21: 0,299
VGMA22: 0,214
VCOM: 6,68
AVDD: 15,42

(V)

Does the low reading on gamma 20-22 indicate a fault?

[vinceroger69]

Re: Sony KDL-40V3000 distorted picture

A lot of those readings look bad from what i understand it should be a steady gradual voltage drop im sure someone more experienced will comfirm

[budm]

Re: Sony KDL-40V3000 distorted picture

Yes, it is bad.

[tom66]

Re: Sony KDL-40V3000 distorted picture

A lot of those readings look bad from what i understand it should be a steady gradual voltage drop im sure someone more experienced will comfirm

Gradual voltage drop or increase, but only ever moving in one direction (Monotonic function)