Westinghouse LD-4055 has dim standby LED, does not respond.

[triplefour]

13 pin connector ALL VOLTS PRESENT WHEN PSON CONNECTED TO 5VSB
--------------------------------------------------------------
1 12v
2 12v
3 GND
4 GND
5 GND
6 5V
7 5V
8 5VSB
9 PSON
10 5V
11 5V
12 GND
13 GND


6 PIN CONNECTOR ALL VOLTS PRESENT WHEN BK CONNECTED TO 5V
-------------------------------------------------------------
1 GND
2 GND
3 ADJ
4 BK
5 12V
6 12V

when tricked with pson and bk connected to 5v sources, backlights come on and stay on.
they seem a bit dim though. maybe too much sunlight in the room?


LED CONNECTORS:
------------------------
2 STRINGS
WITH LED TESTER, BOTH STRINGS READ 26V
but with psu tricked, and measuring the voltage going to the strings,
one string reads 26v and the other reads 56v??


btn board
-------------------
has 3.5v on both signal wires at rest.
pushing buttons changes voltage, specifically it drops the voltage a certain amount on one of the wires
pushing power button does not change the voltage on either wire.

IR/LED board
--------------------
has 5v going to it
but only 1.6v to the LED
LED lights up but seems dim. i could be wrong. maybe thats normal. i havent seen many westinghouse tvs. this is maybe the 3rd one ive ever worked on.
when the ir/led board is disconnected the blue wire coming from the mainboard that goes directly from the connector to the LED on the ir/led board reads at 5v.
LED does not respond (blink, dim, brighten) to any to any button presses.
i programmed a universal remote to both codes it listed for westinghouse, and neither of them had any effect on the tv.



possible LED/IR/BTN board failure? easy fix??

i can find the Mainboard on ebay but not the button board or ir/led board

how can i simulate a power button press to the mainboard with all boards connected (or just the Button board and ir/led disconnected)?

ive tried jumpering the pson to the 5vsb with the mainboard attatched but it had no effect.
i tried all combinations of boards plugged in or not.
having a hard time deciding if its the mainboard or the BTN or LED/IR ...
i really think that if all the other buttons change the voltage on the pins of the button board, but the power button does not, this is definitely a problem with the button board. am i right about that?

help me out if you can. i realize westinghouse is not a very popular brand, but they make a decent tv. better than emerson/funai anyway

[R_J]

Re: Westinghouse LD-4055 has dim standby LED, does not respond.

If the backights stay on when tricked on the power supply and backlights should be good, It could be a bad eeprom on the main board. See shopjimmy.com

The backlights may be dim due to the main not controlling the backlight level.
If you have freeze spray or use an inverted caned air. try freezing the eeprom ic
Unplug the tv, freeze the eeprom - plug in the tv and try to turn on. This sometimes works indicating where the problem is.

[CapLeaker]

Re: Westinghouse LD-4055 has dim standby LED, does not respond.

Well, I kind of agree with R_J. Just the point that where the main board doesn't send PSon bugs me and I'd say it could also be the main IC on the main board. Pull the heatsink off that main IC and see if that is an XD chip. If it is, I am betting on it being bad.

[triplefour]

Re: Westinghouse LD-4055 has dim standby LED, does not respond.

i am not at home so cant look at the tv till later, but i will try both of your suggestions. but isnt it strange that when i push any other button on the button board, i notice a voltage drop on one of the wires, but when i push pwr button, i see no change? doesnt this point to a faulty button?

[R_J]

Re: Westinghouse LD-4055 has dim standby LED, does not respond.

How many wires go to the switch board? I see 2, one red and one black, so if the other buttons change the voltage but the power button does not, it could be the tac switch that is bad, check it with your meter or exchange it with one of the others, they are likely all the same

[triplefour]

Re: Westinghouse LD-4055 has dim standby LED, does not respond.

there are 2 wires. you cant see it in the picture but there is a red, white and black. red and white are the signal wires. half the boards buttons go to the red wire and the other half go to the white.
i cant figure out how to test the switch tho. i thought if i measured for resistance across the switch and then pressed the button i would see it change, but its on OL no matter what scale i use and whether i press buttons or not.

heres some pics of the btn board for reference

[triplefour]

Re: Westinghouse LD-4055 has dim standby LED, does not respond.

after that last post i tried to use continuity mode on my meter to test across the switches, and i do see a change from OL down to .3 on most switches when i push the button (but down to .1 on one of them, and the meter actually beeps) but the pwr switch does appear to be bad. it does not change at all.

guess ill try swap the switches

[budm]

Re: Westinghouse LD-4055 has dim standby LED, does not respond.

See picture.
The processor senses different Voltages from each switch to perform each function, thus difference value resistors.

[R_J]

Re: Westinghouse LD-4055 has dim standby LED, does not respond.

It looks like that menu switch has some rust on it? Those tac switches are prone to failure, they usually go leaky causing functions to change by themselves ie: channels changing, volume going up or down by itself etc.

[triplefour]

Re: Westinghouse LD-4055 has dim standby LED, does not respond.

yea there is a bit of rust on each one of them. ive seen these switches in a lot of different devices. it shouldnt be hard to locate a donor.

[triplefour]

Re: Westinghouse LD-4055 has dim standby LED, does not respond.

well i swapped the pwr switch with the switch next to it, and now the TV turns on! but i have to hold down the button, or press it a few times...it's not perfect. and some of the other switches dont work either. like i cant get into the menu, and i can only turn the volume down. so im thinking i should replace all these switches. shouldnt be too hard. the picture is nice on this tv! and when it turns on, the dim red standby light turns blue. Another one tried to bite the dust but i didnt let it!

i was able to use a LG remote and also a vizio remote to power on and off with no problems, and even turn up and down the volume. the vizio remote even let me get into the menu. but i had to use channel up and down and vol up and down to navigate. what is a westinghouse anyway??

maybe all i needed was the remote :]
hard to believe someone would throw this out just because they lost the remote and couldnt turn it on via btn board.

[neilc6]

Re: Westinghouse LD-4055 has dim standby LED, does not respond.

Those switches are 6x6x4.3mm micro switches. I bought a pack of 100 from China for $1 and only needed one to fix a doorbell. Ended bundling into packs of 20 and selling the extras for $5 on ebay (costs $2 to ship within Canada).

https://www.ebay.com/itm/50pcs-6x6x4...S/123030716744

[triplefour]

Re: Westinghouse LD-4055 has dim standby LED, does not respond.

thanks for the tip. definitely going to be making that purchase. but why would anyone pay 5$ for 20 when they can pay 1$ for 50?

[neilc6]

Re: Westinghouse LD-4055 has dim standby LED, does not respond.

thanks for the tip. definitely going to be making that purchase. but why would anyone pay 5$ for 20 when they can pay 1$ for 50?

Cheap shipping from China takes 3 to 6 months to arrive due to slow customs processing in Canada. Lettermail 3 to 5 days.

[triplefour]

Re: Westinghouse LD-4055 has dim standby LED, does not respond.

ok that makes sense, but still it just doesnt seem like 1 american dollar in china can really be worth the cost (and profit!) of creating, packaging, and shipping 100 little switches.