Measured PC1701 {4}, {5} between pin voltage is 0V, indicate metal halide lamp is not lit, first check the D706, C715, C716, L703 and other components external switching power supply are normal winding S1; road test R903, resistance value R904 normal; then measuring the output of 14V switching power supply voltage is normal, but after 12V regulator IC705 {2} pin output voltage is 0V. Replace the IC705, troubleshooting.rq4service manual download site