I got a new JL Audio 250/1 channel amplifier for my sub. The sub and enclosure hasn't come in yet, but I installed the amp earlier.

First, I disconnected the negative terminal on the battery, and hooked up the positive (red) power cable for the amp. Then, I ran the remote cable back and plugged it into the amp. First, I grounded the 3 foot cable and plugged it in, and then plugged in the power cable.

I went back up front, reattached the negative terminal, and turned the car on. The power light on the amp did not come on. What would cause this?

 

Nevermind. It was the battery. I turned the car on, left it on for a couple of minutes, and the light eventually came on on the amp. Everything's good now.

 

That doesn't make any sense, if there is enough voltage to turn your motor over then there was plenty to power your amp. Did you turn the ignition to acc1 and turn the radio on? If not that's why the amp didn't come on. If you did that, and the amp still didn't come on then you have another problem. Could be a bad ground, or just faulty wiring.

 

I'm going to assume it was the ground because after I grounded it off in a ''better'' spot, it started working.