Acer AL1702 AL1702 Service Guide - Page 17

3. Checking the back light unit AL1702 Is +12V supplied to inverter PWB ? (by the power board) NG OK Failure Point 1) Inverter cable disconnection. 2) Power board failure. Check the BKLT_EN signal of the rectangle input P301 pin 6 at TTL high level. NG OK Failure Point 1) printed wire broke between P301 pin6, R306 and I307pin 31. 2) I307 is failure. Check the BKLT_ADJ signal of the input P301 pin5 from I305 pin73 is a PWM signal. NG OK Failure Point 1) printed wire broke between P301 pin5, Q301, Q302 and I305 pin73. 2) I305 is failure. Failure Point Back light unit of LCD module is failure. Page 15