Boss Audio MR800 User Manual in English - Page 18

Troubleshooting If you experience operation or performance problems with this product, compare your installation with the electrical wiring diagram on the previous pages. If problems persist, read the following troubleshooting tips which may help eliminate the problems. SYMPTOM Amplifier will not power up. Protection LED comes on when amplifier is powered up. No output. Low output. POSSIBLE REMEDY Check to make sure you have a good ground connection. Check that the Remote Input (Turn-On) has at least 3VDC. Check that there is battery power on the (+) terminal. Check that there is at least 12v. Check all fuses, replace ifnecessary. Make sure that the Protection LED is not illuminated. Ifit is lit, shut off the amplifier briefly, and then repower it. Check for short circuits on speaker leads. Turn down the volume control on the head unit to prevent overdriving. Remove speaker leads, and reset the amplifier. If the Protection LED stil comes on, then the amplifier is faulty and needs servicing. Check that all fuses are OK. Check that amplifier is properly grounded. Check that the Remote Input (Turn-On) has at least 3VDC. Check that the RCA audio cables are plugged into the proper inputs. Check all speaker wiring. Reset the Level Control. Check the Crossover Control settings. Audio present in only one channel. High hiss in the speakers. Squealing noise from speakers. Check the RCA interconnect cables. Check all speaker wiring. Disconnect all RCA inputs to the amplifiers. If the hiss disappears, then plug in the component driving the amplifier and unplug its inputs. If the hiss disappears at this point, go on until the faulty/noisy component is found. It is best to set the amplifier's input level control as low as possible. Tho best subjective signal-to-noise ratio is achieved in this manner. Try to se the head unit as high as possible (without distortion) and the amp input level as low as possible. Check for improperly groundedRCA interconnects. Distorted sound. Amplifier gets very hot. Engine noise (static type) Engine noise (alternator whine) Check that the Input Level Control is set to match the signal level of the head unit Always try to set the Input Level as low as possible. Check that all crossover frequencies are properly set Check for short circuits on the speaker leads. Check that the minimum speakerimpedance for the amp modelis correct. Check that there is good air circulation around the amp. In some applications, it may be necessary to add and extemal cooling fan. This is usually caused by poor quality RCA cables,which can pick up radiated noise. Use only the best quality cables, and route them away from power cables. Check that speaker leads are not shorted to the marine vessel chassis. Check that the RCA grounds are not shorted to the marine vessel chassis. Check that the head unit is properly grounded. Marine MOSFET Amplifier User's Manual - page 18