User manual PIONEER GM-X644

[. . . ] Check the connections of the power supply and speakers if the fuse of the separately sold battery wire or the amplifier fuse blows. Detect the cause and solve the problem, then replace the fuse with another one of the same size and rating. To prevent malfunction of the amplifier and speakers, the protective circuit will cut the power supply to the amplifier (sound will stop) when an abnormal condition occurs. In such a case, switch the power to the system OFF and check the connection of the power supply and speakers. [. . . ] If the system remote control wire of the amplifier is connected to the power terminal through the ignition switch (12 V DC), the amplifier will always be on when the ignition is on-- regardless of whether the car stereo is on or off. Because of this, the battery could go dead if the engine is at rest or idle. Speakers to be connected to the amplifier should conform with the standards listed below. If they do not conform, they may catch fire, emit smoke or become damaged. the speaker impedance must be 1 to 8 ohms. But in case of two-channel and other bridge connections, the speaker impedance must be 2 to 8 ohms. Install and route the separately sold battery wire as far away as possible from the speaker wires. Install and route the separately sold battery wire, ground wire, speaker wires and the amplifier as far away as possible from the antenna, antenna cable and tuner. Cords for this product and those for other products may be different colors even if they have the same function. When connecting this product to another product, refer to the supplied Installation manuals of both products and connect cords that have the same function. Subwoofer Other than subwoofer Subwoofer Other than subwoofer Subwoofer Other than subwoofer Subwoofer Other than subwoofer After making all other connections at the amplifier, connect the battery wire terminal of the amplifier to the positive (+) terminal of the battery. External Output If only one input plug is used, do not connect anything to RCA input jack B. The female terminal can be connected to the auto-antenna relay control terminal. If the car stereo does not have a system remote control terminal, connect the male terminal to the power terminal through the ignition switch. Always use the special red battery and ground wire [RD-223], which is sold separately. Pass the battery wire from the engine compartment to the interior of the vehicle. After making all other connections to the amplifier, connect the battery wire terminal of the amplifier to the positive (+) terminal of the battery. Fix the wires securely with the terminal screws. Expose the end of the speaker wires by about 10 mm and twist using nippers or a cutter. You must attach the supplied terminal cover to the speaker output terminal. [. . . ] After installing the amplifier, confirm that the spare tire, jack and tools can be easily removed. 1 kg (Leads for wiring not included) Maximum power output . Cut off frequency: 40 -- 120 Hz Cut off slope: ­12 dB/oct High pass filter . Cut off frequency: 40 -- 120 Hz Cut off slope: ­12 dB/oct Maximum input level/impedance . [. . . ]