Wt7515 bypass !!!!

[SWITCHMOOD]

Hi all !, I'm at that point where I'm thinking of taking the plunge. I have a 26" TECHNIKA LCD26-M3. It has a PSM143-310-2-R power supply. The tv will not power up, I've had the PSU apart and checked all the components. It's got 5v but nothing else. The main board is sending the reset signal but the PSU has the dreaded WT7515 management IC. I'm 80 - 90% comfortable that the rest of the
psu is ok. It's not worth replacing the psu or WT7515. I'm thinking of coupling pin 3 to grnd via a 1k rersistor and pin 14 to pin 13 (5v+) via a 1k resistor (wt7515) and bench testing the psu out of the tv.

is this a wise thing to do, can anyone help please ?

[Toasty]

Re: Wt7515 bypass !!!!

>>has the dreaded WT7515 management IC<<

??

Dreaded?

Which IC version?

These are in -every one- of thousands of Apple iMac PSU's without issues. Only had one bad in 100+ PSUs. That was from a power surge.

I'd bet the problem is elsewhere. Likely the start-up caps.

Have you replaced anything so far?

Photos?
Voltages?
Checked chip datasheet against voltages?

.

[SWITCHMOOD]

Re: Wt7515 bypass !!!!

Thank you Toasty, you have stopped me. I wasn't happy going down that route anyway.

ok, so although I do electronics as a job, I know very little about tv etc diagnosis. I have removed/ tested all the caps on the psu board with a cap meter along with the diodes, opto isolators, transistors (mosfets) and resistors.
I have not tested the DM311 PWM DRIVER or transformers, chokes.

The board is simple as psu's go. I do feel I'm missing something.

I do not have a manual or schmatic, I'm not sure that I want to subscribe to a datasheet web site at the moment.

so, i'm not in tune with tv repairs etc. Can I ask anyone, if you were like me, starting to get serious about tv repairs and short of money, would you go out and buy a peak atlas ESR meter ? and it seems that I need a good source of manuals and schematics, where is the best place to get these ?

can any body help me to see the light ?

[Fedguy]

Re: Wt7515 bypass !!!!

Does anyone know whereto buy the dreaded WT7515 chip?

thx

[Toasty]

Re: Wt7515 bypass !!!!

Why dreaded? What version?

Why do you think it's bad?

[Fedguy]

Re: Wt7515 bypass !!!!

The 5v sense on the chip is there but no output.

I need to buy them do you know where to get it?

[Toasty]

Re: Wt7515 bypass !!!!

Needs all 3 inputs to output.

Still haven't answered question. What version? In what PSU?

[Fedguy]

Re: Wt7515 bypass !!!!

AC/Bel 661-3350

First left green LED comes on Logic board but when you push the power button nothing happens. I have 20v and 5v on the connector.

We traced the voltages on the WT7515 which has the 5v sense in but no 5V out

[Toasty]

Re: Wt7515 bypass !!!!

This belongs in it's own topic, correctly titled.

This topic was a different WT7515 *VERSION* about a LCD TV.

You're talking about an iMac PSU.

Jump to the other topic you started regarding the chip and I'll ask a moderator to re-title that one.

Copy your above post to the other topic first.


Thanks!
Toast

[Fedguy]

Re: Wt7515 bypass !!!!

thx