中文
含义
创维电视检测到 LED 灯条开路故障，E20 代码表示一条或多条 LED 灯条完全断开，驱动回路中无电流通过。与 E1 背光故障不同的是，E20 更具体地指向灯条自身物理开路，而非驱动板或其他电路问题。此故障导致屏幕对应区域完全无背光，典型表现为屏幕局部黑区（对应开路灯条位置）或整屏无背光。创维大尺寸电视通常使用多条 LED 灯条串联或并联，开路一条即可能导致整组背光不亮。
常见原因
- LED 灯珠长时间使用后内部键合线断开（wire bond detachment），灯珠失效开路。
- 灯条 PCB 铜箔走线因电流过载熔断（fuse trace），常见于灯条连接端部。
- 灯条与灯条之间的连接器接触不良或焊点脱焊断开。
- 灯珠受潮内部腐蚀导致电极失效，LED 芯片与焊盘之间开路。
- 灯条安装螺丝过紧导致 PCB 板弯曲，铜箔走线产生微裂纹逐渐发展为开路。
- 背光升压电路异常输出高压浪涌，瞬间烧断灯条上最薄弱的焊点或铜箔。
自助排查
- 用手电筒贴近屏幕照射，在暗环境下观察——如果屏幕局部能看到图像但该区域明显暗于其他部分，对应区域的灯条可能已开路。
- 断电后打开后盖，目测灯条连接器的插头是否松动或线缆是否断开。
- 使用万用表二极管档或电阻档测量各组灯条连接器两端——正常灯条应有正向导通电压（每颗灯珠约 3V），开路则显示 OL（无穷大）。
- 观察灯条外观是否有明显发黄、发黑或 PCB 烧焦痕迹——开路故障的灯条通常能看到物理损坏。
- 灯条更换需要拆解液晶面板模组，操作风险极高且容易损坏面板脆弱的排线，务必联系创维售后专业处理。
English
Meaning
The Skyworth TV has detected an LED strip open-circuit fault. Code E20 indicates that one or more LED strips are completely disconnected, with no current flowing through the driver circuit. Unlike E1 (general backlight fault), E20 more specifically points to a physical open circuit in the strip itself rather than a driver board or other circuit issue. This fault causes complete loss of backlight in the corresponding screen area — typically showing a localized dark zone or a completely dark screen. Large-size Skyworth TVs typically use multiple LED strips in series or parallel configuration; a single open strip can disable the entire backlight assembly.
Common Causes
- The internal wire bond in an LED bead has detached after extended use, causing the bead to fail open.
- The copper trace on the strip PCB has fused open due to current overload, commonly seen at the strip terminal ends.
- The connectors between strips have poor contact or the solder joints have detached.
- Moisture ingress has caused internal corrosion of the LED bead electrodes, creating an open circuit between the LED chip and the pad.
- Over-tightened mounting screws have bent the strip PCB, creating micro-cracks in the copper traces that gradually develop into open circuits.
- The backlight boost circuit has output an abnormal high-voltage surge, instantly fusing the weakest solder joint or copper trace on the strip.
Self-Check Steps
- In a dark room, shine a flashlight close to the screen — if you can see an image but an area is noticeably darker than the rest, the LED strip in that zone may be open.
- With power off and the back cover removed, visually inspect the strip connectors for loose plugs or disconnected wiring.
- Using a multimeter in diode or resistance mode, measure across each strip connector pair — a normal strip shows forward voltage (about 3V per LED bead), while an open strip shows OL (over-limit).
- Inspect the strips for visible yellowing, blackening, or burn marks on the PCB — an open strip can often be identified by physical damage.
- LED strip replacement requires disassembling the LCD panel module — this carries very high risk and can easily damage the delicate panel ribbon cables. Contact Skyworth after-sales service for professional handling.