bush model nu-lcd32tv022hd

[multimeter]

ok,im trying to fix this tv,symptoms are...

1,tv powers on from stanby to green light
2,screen backlights come up,and stay on
3,no picture but sound(running through ps3)on hdmi input
4,no other symptoms
tested so far...
1,power supply outputting proper voltages
2,caps fine ,and esr tested on psu
3,immediatley thought t-con board,checked f1 (smd) marked as "k" on 200 ohm setting,tested less than 30 ohm,(0.01),i have found what i think could be another fuse, this is smd also and is marked as "e" but im not sure if this is a fuse?the f1 fuse and the mystery fuse are both white in color,the mystery fuse,on 200 ohm dmm is measuring "1" on my meter,"1" on 2k,20k,but on the 200k setting the reading starts to rise from 0.086 and keeps rising.
im unable to post up pics as i dont have a decent camera until 2 wks time,any initial thoughts?

[multimeter]

Re: bush model nu-lcd32tv022hd

i forgot to add,there are no on screen menu as well as no picture..

[retiredcaps]

Re: bush model nu-lcd32tv022hd

i have found what i think could be another fuse, this is smd also and is marked as "e" but im not sure if this is a fuse?

Is there a pcb designation by this chip?

[multimeter]

Re: bush model nu-lcd32tv022hd

Is there a pcb designation by this chip?

there is r608 next to it wether that is for this mystery fuse im not sure,but i initialy thought it was a smd resister,but havent seen a white one with the marking"e"on it,they normally represent a fuse

[multimeter]

Re: bush model nu-lcd32tv022hd

ok tried elektrotania for schematic/service manual but cant seem to find it on there,anyone know other sites i can try?

[tom66]

Re: bush model nu-lcd32tv022hd

Would it happen to be a Megmeet supply? Replace the two 1000u/10V near the top of the supply board for standby, and the 1000u/35V cap which provides inverter power. Use low ESR long life, I used Panasonic FM (standby) and Chemicon KZE (for inverter.)

If that fails, check inverter... it's pretty tricky to get to from what I remember (I'm glad I didn't need to get to it to repair an LCD37TV016HD.)

[multimeter]

Re: bush model nu-lcd32tv022hd

Would it happen to be a Megmeet supply? Replace the two 1000u/10V near the top of the supply board for standby, and the 1000u/35V cap which provides inverter power. Use low ESR long life, I used Panasonic FM (standby) and Chemicon KZE (for inverter.)

If that fails, check inverter... it's pretty tricky to get to from what I remember (I'm glad I didn't need to get to it to repair an LCD37TV016HD.)

no,its a 17pw15-8 which if memory serves me right its a vestel ,im swaying away from checking the inverter at the moment, as the backlights work fine no flickering etc,frustrating as i dont have a camera to put pics up grrr,hopefully next week,im goin to recap the output lytics as a matter of course with fc's anyway,it seems the problem is pointing towards t con

[tom66]

Re: bush model nu-lcd32tv022hd

no,its a 17pw15-8 which if memory serves me right its a vestel ,im swaying away from checking the inverter at the moment, as the backlights work fine no flickering etc,frustrating as i dont have a camera to put pics up grrr,hopefully next week,im goin to recap the output lytics as a matter of course with fc's anyway,it seems the problem is pointing towards t con

Vestel makes me want to

Check T-con fuse.

[multimeter]

Re: bush model nu-lcd32tv022hd

Vestel makes me want to

Check T-con fuse.

t con fuse is fine,on further investigation on the power supply ,it seems to be riddled with dry/cracked joints,even one of the primary side caps legs just wiggled loose and came out,so going to scan the entire rear side of psu and reflow as needed,that will teach me to be lazy!,there arnt any voltage legends on the output conns,so going to have to try and find the schematic for this psu to get the voltages ,il update when finished on psu

[mu2]

Re: bush model nu-lcd32tv022hd

Hi,

Not sure if this helps but here goes. I'm working on a Visco VSC-32V1 that I think may have the same mainboard. My problems are similar - power supply voltages are exact, backlights come up - but the screen is gray not blue. T-con fuse is fine. Haven't checked for sound since there isn't a menu.
The mainboard has a number 200-107-GF371XC-BH Rev. B - manufactured 8-12-2006, this number is located below U11. I checked the esr of the caps and the fixed and adjustable ldo regulators. The adjustable regulators have some odd voltages but if you check the resistor values and plug into the formula they are dead on!. The only odd thing I found so far is that there are two fixed ldo regulators on the right side near the crystal. The lower one is 1.8 vots and it's correct, the upper one is U5 is a AS1117L-33 which should be a 3.3 volt. It is reading 3.8 volts.
I don't have one to try but intend to order it.
If you have the same board, see what the output of U5 measures.

Mike

[tom66]

Re: bush model nu-lcd32tv022hd

Above poster, do you get any picture at all with colours messed up or just a grey screen?

[mu2]

Re: bush model nu-lcd32tv022hd

Only getting a gray screen.

Mike

[multimeter]

Re: bush model nu-lcd32tv022hd

Hi,

Not sure if this helps but here goes. I'm working on a Visco VSC-32V1 that I think may have the same mainboard. My problems are similar - power supply voltages are exact, backlights come up - but the screen is gray not blue. T-con fuse is fine. Haven't checked for sound since there isn't a menu.
The mainboard has a number 200-107-GF371XC-BH Rev. B - manufactured 8-12-2006, this number is located below U11. I checked the esr of the caps and the fixed and adjustable ldo regulators. The adjustable regulators have some odd voltages but if you check the resistor values and plug into the formula they are dead on!. The only odd thing I found so far is that there are two fixed ldo regulators on the right side near the crystal. The lower one is 1.8 vots and it's correct, the upper one is U5 is a AS1117L-33 which should be a 3.3 volt. It is reading 3.8 volts.
I don't have one to try but intend to order it.
If you have the same board, see what the output of U5 measures.

Mike

i havent got to the main board yet,just getting through sorting corrections on psu,but yeah will check them out,the 1117 ldo's are very unrealiable,when you measured the adjustable regs did you make sure your + on dmm is on the large tab ?this is the output for a adj reg,i think a suitable part for your reg is the lm1117-3.3,others may enlighten

[mu2]

Re: bush model nu-lcd32tv022hd

Multimeter,

I got the Visco tv working again.
I replaced two fixed 3.3 volt ldo regulators on the main board - They both measured 3.8 volts. The was a third on the board but it measured fine.
I believe these were parts U-5 and U-7. Also replaced the caps in the vicinity of these regulators. Seem to recall them being 47 uf and 100 uf.
The other part I replaced - probably the main culprit - was a Nikos L1117DG on the t-con board. Sorry, I didn't write the pcb reference number down before I closed it up. This is an adjustable type ldo regulator.
Hope this helps someone.

Mike