I have an Dual brand 300 watt amplifier that I just bought and I hooked everything up right (battery---power, ground----sanded metal, bypassed remote with toggle switch remote-----+terminal on switch ground---- -terminal on switch) but it still wont turn on and I have checked the fuse in line with power and fuse on amp?

The remote wire DOES need to be connected to the head unit. You can see if thats the problem simply by touching the remote wire to the power wire. The unit should come on. The head unit should either have a remote lead, or a power antenna lead, and thats what you need to turn the amp on and off. BE SURE your ground is solid, and its usually best to take that to the battery as well to prevent unwanted engine noise. Hope this helps!

Hello
If your Dual Car Amp refuese to switch ON check the following.
+12V wire is not connected or incorrect voltage.
REM wire is not connected or incorrect voltage.
Ground wire is not connected.
Fuse(s) are blown.
If the fuse blows repeatedly, check whether the +ve voltage wire touche the chasis of the vehicle. If it is OK, the fault is with the univt itself. That is, the output of the unit has a short. Check for any output IC failure. OK.

Check all your cable work.
Power is connected tight? Ground is attached tight - on both ends (my guess is it is the ground) Remote cable?
Is the ground a proper ground?

try runing the remot to the battery and c wat it does

you shouldn't need a diagram all you need is these items here.

purchase a 4gauge wiring kit

run a a power line from battery to amp with a in line fuse 6in from battery.

run a ground from car frame to amp. ( scratch paint and screw it down with an eyelet for good contact)

run a remote from radio to amp.(blue wire)

run rca's from the radio to the amp ( sub input on back of radio)

finally connect your speakers.

first you need to run a power cable for the battery to where ever you are going to place the amp DO NOT hook the cable to the battery until the very last just wire it to the amp for now.next you will want to ground your amp hook the ground wire to the amp and the other end to a solid piece of metal in the car this is very important if you don't get good metal on metal contact you'll blow a fuse. If you can hide it well strip back a bit of carpeting and use sand paper to remove all paint from the metal and drill a hole for a screw. once that is finished you will need to run a remote wire from the amp to the car stereo usually these are the blue wire on the harness in the dash. once that is hooked up run the rca cables (reds and whites) plug in to amp and then in to back of cd player. once this is all hooked up and fully secure hook the power cable to the battery make good contact and if everything is grounded right you should get the lights on in the amp. Next step hook up the speakers run speaker wire from the amp to your speakers make sure negative goes to negative and positive to positive or you'll get clipping and it will sound like ****. that's pretty much the jist of it. if you have any questions let me know.

DISCONNECT THE GROUND WIRE. SAND ALL THE PAINT FROM THAT AREA AND REGROUND IT. WHAT I WOULD RECOMMEND IS DRILLING A HOLE THROUGH THAT TRUNK, SAND THE PAINT AWAY FROM WHERE THE GROUND WIRE WILL GO AND BOLT THE GROUND WIRE TO THE TRUNK BOTTOM. THE PAINT WILL CAUSE THE AMP NOT TO GET A SOLID GROUND

With your multimeter set to DC volts, the black meter probe on the ground terminal of the amp (not on the point where the ground wire connected to the vehicle) and the head unit on (so the amp will have remote voltage applied), touch the red probe alternately to the B+ and remote terminals of the amp. If the voltage is below ~11 volts, you need to check the wiring feeding whichever line is too low.

Let me know if you have any other questions.

ur remote wire needs to be hooked up to the spot marked remote on the amp....and ground to the ground slot..if that is done check the fuses on the amp or check the fuse under the hood from your power wireif it still wont come on..make sure ur ground is touching a good metal area sand around the area if needed this should sole ur problem

check remote voltage first?