MB QUART QAA1000 Amplifier Does Not Turn On, No Sound Coming From Amplifier, Troubleshooting

Models: QAA1000

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OPERATION

1.Turn volume on head unit to minimum.

2.Disable any signal enhancement systems (i.e. external processors, bass and treble controls set to 0, Loudness OFF, etc).

3.Disconnect speakers from amplifier output terminals.

4.Turn Gain to minimum on all channels.

5.Set input sensitivity switch(s) to HIGH.

6.Set the LOAD switch to correspond to your speaker load (2 or 4-Ohm).

7.Insert the test disc (use a 45Hz test tone for subwoofer applications and a 1kHz for midrange and tweeter applications at the appropriate level (see above note)).

8.Turn volume on the head unit up to the loudest desired listening level (typically around 3/4 of maximum) some source units will not clip even at max volume with an all high bits signal, if your source unit has these high performance characteristics, turn the volume to maximum.

9.Rotate the gain adjustment wheel to the right until the LED Clip indicator changes from green to orange.

10.Back the gain down to the point where the LED returns to green again (if the gain is at its maximum and the Clip indicator has not turned orange yet, lower the gain to minimum, set the sensitivity switch to LOW and repeat step 9).

11.The value on the READ display now shows the amount of amplification required in decibels, you can rotate the other gain adjustment wheel (on 2 and 4-channel models only) until gain values match.

If the load impedance selector switch is reconfigured following this gain setup process, please repeat the process, failure to do so will result in inaccurate clipping levels and may clip early or late by 3 dB! The difference in load impedance will cause the signal to clip at different voltages but will always maintain the same power level.

TROUBLESHOOTING

Amplifier Does Not Turn On

Possible Cause

The in-line fuse on battery positive cable is blown.

Poor ground connection

Poor power connection or power outside acceptable range.

Solution

Check in-line fuse on battery positive cable. Replace if necessary.

Verify that Ground connection is connected to clean metal on the vehicle’s chassis. Repair/replace if necessary.

Verify there is 10.5 - 15.5 Volts present at the positive battery and remote turn-on cable. Verify quality connections for both cables at amplifier, stereo, and battery/fuseholder. Repair/replace if necessary.

No Sound Coming From Amplifier

Possible Cause

Poor RCA connections.

Solution

Verify good RCA input connections at source and amplifier. Check entire length of cables for kinks, splices, etc. Test RCA inputs for AC voltage with the source unit on. Repair/replace if necessary

Poor speaker connections

Bad source unit

Use an ohm meter to check speaker wire integrity. Check entire length of wires for kinks, splices, etc. Repair/replace if necessary.

Connect RCA input from test source directly to amplifier input. If this solves the problem, have the source unit repaired or replaced. If not, have the amplifier checked by a qualified technician.

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MB QUART QAA1000 Amplifier Does Not Turn On, No Sound Coming From Amplifier, Troubleshooting, Possible Cause, Solution