Samsung LE40R88BD blank screen

[mikcle60]

Hello all i have a Samsung LE40R88BD which has been giving me bother for some time now, to start with the caps blew so my uncle replaced then and the tv worked for a couple of weeks then it started clicking again so he replaced the eeprom which solves the problem and the tv worked for a a month of so, now the tv when turned on the screen is completely blank and the blue light flashes 5 times the the tv eventually goes off. I've taken voltages from psu to main board connector
1- 1.96v
2 - 0
3 - 5.16
4 - 0
5 - 0
6 - 0
7 - 11.95
8 - 11.95
9 - 0
10 - 0
11 - 0
12 - 0
13 - 5.58
14 - 5.58
15 - 5.58
16 - 5.58
17 - 0
18 - 0
19 - 14.05
20 - 0
21 - 14.15
22 - 14.15
23 - 0
24 - 0

Which i think all seem ok?

The voltages from CNI803 which i think is for the inverter!!

Inverter on/off - 0.04/0.03v
dim - 3.48v
Nc - 0.0v
Gnd - 0.0v
DET _5v - 5.59v

I would of thought the inverter on/off voltage shout be greater?

Any help is greatly appreciated

[mikcle60]

Re: Samsung LE40R88BD blank screen

[mmartell]

Re: Samsung LE40R88BD blank screen

Yes you are not getting the inverter turn-on signal but it's possibly due to some other problem. Is the flashing blue light on the front of the panel ? Maybe it's an error code.

You will need to post a picture of your PS where the labels can be seen to match up with the voltages you've posted to see if any are missing/out-of-spec.

Someone with more knowledge will come along be patient.

[budm]

Re: Samsung LE40R88BD blank screen

Pictures of the whole backside of the board, this TV has the Balancer board on the left side looking from the back.

[mikcle60]

Re: Samsung LE40R88BD blank screen

Hi thanks for the replys folks, I here is some more pictures hope they are of use







Could the caps be gone again even tho they aren't bulging?

[newtothis]

Re: Samsung LE40R88BD blank screen

Could the caps be gone again even tho they aren't bulging?

Yes, need an ESR meter to really check mindya

[budm]

Re: Samsung LE40R88BD blank screen

"Inverter on/off - 0.04/0.03v" OK, monitor this pin to see if it even changes state at all before the LED starts flashing.

[mikcle60]

Re: Samsung LE40R88BD blank screen

Will check it once I replace a fuse I accidentally blew!! I'm pretty sure that when the flashing stopped and relay clicked off the voltage jumped up to around 12v then started dropping but I will double check this when I get the fuse. thanks again

[mikcle60]

Re: Samsung LE40R88BD blank screen

I decided to change the power board as it kept blowing fuses and with the new one fitted the same problem occurs, so I guess this takes the problem away from the power board. could the eeprom be corrupt again?

[mikcle60]

Re: Samsung LE40R88BD blank screen

Reset the eeprom and the tv is working again