FAQ
TL;DR: In 100 % of 9 inspected Philips 55PUS6754/12 sets, the dark-screen defect came from LED backlight strip links; “all strips to be replaced with NEW!” [Elektroda, marian pazdzioch, #20199096; Electroda, Wojtek M, #20242913].
Why it matters: Replacing a €65–130 strip kit can rescue a €500 TV otherwise headed for recycling.
Quick Facts
• Symptom: single backlight flash, sound OK, no menu [Electroda, jack49, #19870224]
• Average failure age: ≈ 2.5 years (30 months) [Electroda, jack49, #19921203]
• LED strip kit price: 300–600 PLN (€65–130) [Electroda, jack49, #19921182]
• Repair success rate after strip swap: 9/9 units fixed [Electroda, marian pazdzioch, #20199096]
• Panel removal risk: high; some panels are glued to the frame [Electroda, elmo071, #20242439]
Why does my 55PUS6754/12 have sound but no picture with a brief flash?
A failed LED backlight opens the circuit. The driver then shuts down, leaving audio active and one startup flash visible [Electroda, jack49, #19870437].
How can I confirm the backlight is bad?
Play a channel in a dark room and shine a flashlight on the screen. If you see the picture faintly, the panel and T-Con work; only the backlight is dead [Electroda, Wojtek M, #19870403].
Are the T-Con board and inverter the same part?
No. The T-Con drives video data to the LCD; the inverter/LED driver powers the backlight. They are separate boards in this Philips chassis [Electroda, Wojtek M, #19870551].
What voltage should I read on the LED connector?
Expect 120–180 V DC when the driver starts; it drops to near 0 V when it enters protection after detecting an open strip (typical LED driver spec, Datasheet-LB-GM3030).
Should I replace one strip or the entire set?
Replace the full set. Mixing old and new strips raises current imbalance and early burnout; experts report repeat failures when only singles are changed [Electroda, elmo071, #20242439].
How much does professional repair cost?
Forum users paid about 600 PLN (€130) for strip replacement, parts and labor included [Electroda, jack49, #19921182].
Can I swap the strips myself?
Yes, with care. 1. Remove rear cover and disconnect speaker & ribbon cables. 2. Detach bezel and gently lift the 55-inch panel onto a flat padded table. 3. Replace all LED strips, reassemble, and test. "Handle the glass like an egg" [Electroda, elmo071, #20242439].
What can go wrong during DIY repair?
Cracking the panel (≈ 1500 PLN replacement) or creating uneven backlight due to frame tension are common edge-case failures [Electroda, jack49, #19870383].
Where can I buy compatible strips?
A verified kit (LB-GM3030-GJ0D22555X10AN22) is sold by Elwron at the link shared in post #19926426 [Electroda, master250, #19926426].
Do other Philips 55-inch models share this issue?
Yes; models 55PUS7504, 55PUS7855, 55PUS7304, and 55PUS7394 use the same strip type and show similar backlight failures [Electroda, master250, #19926426].
How long do replacement strips last?
Quality OEM strips run 20 000–30 000 h at 100 cd/m² brightness—about 8 years of typical viewing (Osram LED Lifetime). Reduce backlight level to extend life.
Will a firmware update prevent backlight failure?
Firmware controls dimming but cannot fix heat-related LED wear. Lower brightness in settings after repair to reduce thermal stress [“Philips TV FAQ”, 2022].