This is my first post on this forum, and my first attempted repair of a modern flat-screen LCD-TV (though I have repaired a few LCD-monitors, all with Elco-problems (high ESR). I have repaired my fair share of TV-sets and VCRs in the past ('90s) and was fairly familiar with the different Philips chassis (KT-3M, K12, K2, K3, K7 are some that come to mind). So I have a fair bit of experience on old sets. Obviously, modern TV sets are quite a different cup of tea.... no HOT or flyback-transformer inside, for starters....
The set came into my possession by accident, for parts. ('you dabble in electronics, perhaps parts from this TV will be of use to you', was the comment.) I have no further information on prior history or problems with the set.
The TV is a Philips 50PUS6262/12 (chassis TMP17.7E LA), judging from the date codes on the ICs it was produced in 2017. I have found the service manual for this set on this forum https://www.badcaps.net/forum/attach...2&d=1622724712.
The TV-set responds to turning on by remote-control: backlight turns on, red standby light goes out. However, nothing appears on the screen. (fully black, with backlight shining 'through').
The decorative LEDs (Ambiance lights) in the back of the TV turn on and respond to the remote-control.
When turning off, the backlight goes out and the red stand-by LED turns on, as should be. Ambiance LED-lights turn off a few seconds later.
All voltages on the Power Supply board measure ok (apart from a missing 3.5V, which seems to be normal for this set, according to other posts in this forum).
I have not checked the elco's for ESR; none appear bulged (not a guarantee, I know) and all the voltages check out ok. I will however check ESR and report back.
The two green LEDs on the computerboard/mainboard do light up constantly. I assume this is normal/expected behaviour.
- just about all mounting screws (from both powersupply board and mainboard) were rather loose. I tightened these, hoping a bad ground was the issue. I didn't notice any different behaviour from the TV set after this.
- When I was fiddling about with the boards (bending, pressing, checking for bad contacts) suddenly a loud bell-sound was heard (old-fashioned doorbell, ring-sound). This startled me a bit. Not sure what's the purpose of that sound. It happened a few times more.
- Have sprayed copious amounts of freeze-spray on the various boards in an attempt to locate a thermal problem. I did not observe any effects.
- When disconnecting the cables going to and coming from the 'small board in the lower middle', i.e. the one that interfaces the mainboard/computerboard to the two screenboards, the screen turns entirely white for a fraction of a second.
- When checking with the Thermal Imaging Camera, no obvious faults were spotted. No semiconductors that got very hot or remained very cold. The large heatsink on the mainboard/computerboard got warm, so it appears to be not entirely dead.
- When entering Service Alignment Mode (SAM) by pressing code '062596 OK' with the remote control, nothing appears on the display, but the backlight gets visibly brighter. Obviously, the computerboard is responding to this particular code.
- when trying to enter Consumer Service Mode (CSM) by pressing '123654' nothing appears to be happening. The backlight doesn't get brighter.
- When entering Factory Mode by pressing 'menu/home 1999 back/return' on the remote control, the backlight does get brighter. So something is recognized and the mainboard is responding to this code. However, nothing is displayed on the screen.
- When turning the TV on and off, I don't notice any new WIFI signal/network appearing on my laptop. Not sure if this is normal/expected behaviour.
- I'm not sure how to check the error-codes using the blinking-LED procedure. When I enter Service Alignment Mode (SAM) using '062596 OK', no LEDs start blinking. Not sure if this means there are no error-codes, or that I haven't followed the proper procedure to start error-code readout. The service manual isn't very clear to me here.
At the moment my suspicion/gut-feeling is indicating the small blue PCB in the lower-middle, the one that interfaces the mainboard/computerboard to the two LCD-screen boards. I did try re-flowing the solderjoints on this board by heating with a hot-air gun. No effects were observed. I may have not heated long/warm enough though, as I'm wary of causing damage, especially without knowing if I'm 'barking up the right tree' by suspecting that PCB.
Any help from people on this board who have experience repairing these more modern TV sets would be greatly appreciated! I'd love to get this TV working again, it would make a welcome addition in the living room for me.
The set came into my possession by accident, for parts. ('you dabble in electronics, perhaps parts from this TV will be of use to you', was the comment.) I have no further information on prior history or problems with the set.
The TV is a Philips 50PUS6262/12 (chassis TMP17.7E LA), judging from the date codes on the ICs it was produced in 2017. I have found the service manual for this set on this forum https://www.badcaps.net/forum/attach...2&d=1622724712.
The TV-set responds to turning on by remote-control: backlight turns on, red standby light goes out. However, nothing appears on the screen. (fully black, with backlight shining 'through').
The decorative LEDs (Ambiance lights) in the back of the TV turn on and respond to the remote-control.
When turning off, the backlight goes out and the red stand-by LED turns on, as should be. Ambiance LED-lights turn off a few seconds later.
All voltages on the Power Supply board measure ok (apart from a missing 3.5V, which seems to be normal for this set, according to other posts in this forum).
I have not checked the elco's for ESR; none appear bulged (not a guarantee, I know) and all the voltages check out ok. I will however check ESR and report back.
The two green LEDs on the computerboard/mainboard do light up constantly. I assume this is normal/expected behaviour.
- just about all mounting screws (from both powersupply board and mainboard) were rather loose. I tightened these, hoping a bad ground was the issue. I didn't notice any different behaviour from the TV set after this.
- When I was fiddling about with the boards (bending, pressing, checking for bad contacts) suddenly a loud bell-sound was heard (old-fashioned doorbell, ring-sound). This startled me a bit. Not sure what's the purpose of that sound. It happened a few times more.
- Have sprayed copious amounts of freeze-spray on the various boards in an attempt to locate a thermal problem. I did not observe any effects.
- When disconnecting the cables going to and coming from the 'small board in the lower middle', i.e. the one that interfaces the mainboard/computerboard to the two screenboards, the screen turns entirely white for a fraction of a second.
- When checking with the Thermal Imaging Camera, no obvious faults were spotted. No semiconductors that got very hot or remained very cold. The large heatsink on the mainboard/computerboard got warm, so it appears to be not entirely dead.
- When entering Service Alignment Mode (SAM) by pressing code '062596 OK' with the remote control, nothing appears on the display, but the backlight gets visibly brighter. Obviously, the computerboard is responding to this particular code.
- when trying to enter Consumer Service Mode (CSM) by pressing '123654' nothing appears to be happening. The backlight doesn't get brighter.
- When entering Factory Mode by pressing 'menu/home 1999 back/return' on the remote control, the backlight does get brighter. So something is recognized and the mainboard is responding to this code. However, nothing is displayed on the screen.
- When turning the TV on and off, I don't notice any new WIFI signal/network appearing on my laptop. Not sure if this is normal/expected behaviour.
- I'm not sure how to check the error-codes using the blinking-LED procedure. When I enter Service Alignment Mode (SAM) using '062596 OK', no LEDs start blinking. Not sure if this means there are no error-codes, or that I haven't followed the proper procedure to start error-code readout. The service manual isn't very clear to me here.
At the moment my suspicion/gut-feeling is indicating the small blue PCB in the lower-middle, the one that interfaces the mainboard/computerboard to the two LCD-screen boards. I did try re-flowing the solderjoints on this board by heating with a hot-air gun. No effects were observed. I may have not heated long/warm enough though, as I'm wary of causing damage, especially without knowing if I'm 'barking up the right tree' by suspecting that PCB.
Any help from people on this board who have experience repairing these more modern TV sets would be greatly appreciated! I'd love to get this TV working again, it would make a welcome addition in the living room for me.
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