Pheonix Gold QX 4150 !

Pheonix Gold Qx 4150 amp. Near new condition, Does have one screw missing on back (as seen in pictures, Il have a look in car as it maybe in there) Powers up but goes straight to protect mode, have not got a clue with electrics? Cost 300 new. Dont know how to price it now. After offers ? The Phoenix Gold QX 4150 has 75 Equalizer Bands. Signal to Noise Ratio: 75 Decibels. Key Features RMS Power at 2 Ohms 1 W x 74 + 100 W x 1 Performance Signal to Noise Ratio 75 dB THD at Rated RMS Power 600 % Crossover / Equalizer Bass Boost Frequency 30 Hz High - Pass Frequency 150 Hz - 20 Hz Other Features Input Voltage 12 volt Dimensions Width 45 in. Height 2 in.