Hello, I have a A1502 with a 820-4924-A that is working well when plugged in Display Port on external display. With internal display plugged in I have no image on it (but still on external display). The Apple Logo on the back cover is ON when the OS boot is over and I have PPVOUT_S0_LCDBKLT = 40V, which supposed to mean that the LCD is not seen. The LCD is not cracked and both connector and cable looks good. The board also looks good.
So far, I have replace the LCD cable, the LCD assembly and finally the LCD connector, still have PPVOUT_S0_LCDBKLT = 40V
Here some measurement on J8300 :
- PPVOUT_S0_LCDBKLT = 40V
- PP3V3_S0_EDP_R = 3.3V
- PP5VR3V3_SW_LCD = 5V
- PP3V3_S0_LCD = 3.3V
- I2C_TCON_SCL = 0V
- I2C_TCON_SDA = 0V
- DP_INT_ML_P<0> = 0V as <1>, <2>, <3>
- DP_INT_ML_N<0> = 0V as <1>, <2>, <3>
- DP_INT_ML_C_P<0> = 0.46V as <1>, <2>, <3>
- DP_INT_ML_C_N<0> = 0.46V as <1>, <2>, <3>
No short on J8300, FL8300 to FL8303 seems fine, all DP_INT_ML lines have continuity. Could 40V on PPVOUT be a logic board problem or is it often because of the display/connector ?
Thank you for your help, I really hope the problem doesn't come from U0500.
So far, I have replace the LCD cable, the LCD assembly and finally the LCD connector, still have PPVOUT_S0_LCDBKLT = 40V
Here some measurement on J8300 :
- PPVOUT_S0_LCDBKLT = 40V
- PP3V3_S0_EDP_R = 3.3V
- PP5VR3V3_SW_LCD = 5V
- PP3V3_S0_LCD = 3.3V
- I2C_TCON_SCL = 0V
- I2C_TCON_SDA = 0V
- DP_INT_ML_P<0> = 0V as <1>, <2>, <3>
- DP_INT_ML_N<0> = 0V as <1>, <2>, <3>
- DP_INT_ML_C_P<0> = 0.46V as <1>, <2>, <3>
- DP_INT_ML_C_N<0> = 0.46V as <1>, <2>, <3>
No short on J8300, FL8300 to FL8303 seems fine, all DP_INT_ML lines have continuity. Could 40V on PPVOUT be a logic board problem or is it often because of the display/connector ?
Thank you for your help, I really hope the problem doesn't come from U0500.