中文
含义
康佳电视检测到面板 VGH(栅极高电平)电压异常。E002 错误代码表示 T-Con 或逻辑板产生的 VGH 电压超出正常范围。VGH 电压用于驱动液晶面板薄膜晶体管(TFT)的栅极开关,该电压异常将导致屏幕显示异常或完全无显示。
常见原因
- 逻辑板上的 DC-DC 转换芯片(如 TPS65193、MAX17126)损坏,无法产生正确的 VGH 电压。
- VGH 电压输出端的电容老化漏液或容量下降,导致电压纹波过大。
- 液晶面板内部栅极驱动电路(Gate Driver)短路,拉低 VGH 电压。
- 逻辑板与液晶面板之间的 COF 排线(TAB)接触不良或断裂。
- 电源板提供给逻辑板的供电电压异常,导致 DC-DC 转换无法正常工作。
- 逻辑板 VGH 升压电路中的二极管或电感损坏。
自助排查
- 断电重启电视,观察故障是否仍然存在——偶发性的电压检测误报可以通过复位清除。
- 检查逻辑板上的排线是否插紧,重新插拔逻辑板与屏幕连接的排线(需断电操作)。
- 观察屏幕表现:若屏幕上半部分或顶部横线区域正常、下半部分异常,常与 VGH 电压不足相关。
- VGH 电路涉及精密 SMD 元件,非专业工具无法测量,建议联系康佳售后更换逻辑板或维修面板。
English
Meaning
The Konka TV has detected an abnormal VGH (gate high-level) voltage on the panel. Error code E002 indicates that the VGH voltage generated by the T-Con or logic board is outside the normal range. VGH drives the gate switching of TFTs in the LCD panel; an abnormal VGH voltage will cause display issues or a completely blank screen.
Common Causes
- The DC-DC converter chip (e.g. TPS65193, MAX17126) on the logic board is damaged and cannot produce the correct VGH voltage.
- Capacitors on the VGH output have aged, leaked, or lost capacitance, causing excessive voltage ripple.
- An internal short in the gate driver circuit of the LCD panel is pulling down the VGH voltage.
- Poor contact or breakage in the COF (TAB) ribbon cable between the logic board and the LCD panel.
- Abnormal supply voltage from the power board to the logic board, preventing proper DC-DC conversion.
- The diode or inductor in the VGH boost circuit on the logic board is damaged.
Self-Check Steps
- Power cycle the TV and check whether the fault persists — intermittent detection false alarms may clear with a reset.
- Check whether the ribbon cables on the logic board are firmly seated; reseat the cables connecting the logic board to the screen (always power off first).
- Observe the screen: if the top half or a horizontal strip at the top appears normal while the rest is not, this often points to insufficient VGH voltage.
- VGH circuits involve precision SMD components that cannot be measured without specialized tools. Contact Konka after-sales service for logic board replacement or panel repair.