Hey guys, I am running into a weird sub problem. I put a system In a friends car about 2 years ago and it has play this entire time until recently his sub stopped working. I figured maybe subwoofer went bad or the amplifier did. Checked the subwoofer in my car and subwoofer still hits and good clear bass. I checked that amplifier and noticed that the amp is in protect mode (this amp is an Obcon 2000i) so he went and bought another ampifier before trouble shooting new amp is apline mrp-m1000. Swapped all wires and cables over to the alpine amplifier and still no sounds from subwoofer . So i started to trouble shoot the system and see if maybe the wiring was bad. I checked my power from the battery cable to ground and I have 12 volts when the car is off and 14 when the car is running. Then I checked the ground cable and had the same results ground cable is good. I checked my remote wire and I have 11 volts just under 12. I checked my rca cables resistance and only had .02 ohms through each cable. I installed the power and ground to the amplifier and I only get 7 volts and it slowly climbs when its connected to the amp. remote stays around 12 volts. All of my fuses are good. I checked the headunit and made sure all subwoofer outputs were turned up and on all the way (headunit is ajvc kds36). I am stumped as to why the system isnt working at all. Can anyone help me and point me in the right direction? Please? Thanks If you have any question im sure I have left out some of the stuff I have done and checked

 

7 volts at the Amplifier is a issue!
Did you actually test the fuses, or just look at them? What size is the power/ground cable, how long is it?

 

Actually tested the fuses. It has 12 volts until I connect it to the amplifier then it drops and slowly climbs until it gets to 11 or 12 when the car is off. Its an 8 gauge power and ground. Probably about 5 to 6 feet long power and 1.5 feet ground.

 

What kind of fuse? If it's an AGU fuse, replace it with a different type such as ANL (wafer) as AGU are known for heating up, causing the solder inside to melt and harden in a different way such that the fuse now has high resistance and will not allow the proper current through. The effect you describe sounds like the capacitors in the amp are "trickle charging" through the power lead and as they become charged, the resistance increases and the current needed from the car decreases (until the capacitors discharge, which would happen if you're actually using the amp).

Where is the amp ground? Is there any corrosion there?

 

No corrosion on the ground its at the trunk latch bolt, I pulled to see if there was corrosion or if the wire was just loose, but it wasnt and there was none. This car has me confused lol. Its just a regular fuse not an AGU or ANL. but one of the bigger ones that scoshe uses.

 

Maxi? Midi?

 

Its a maxi fuse.