Two amps, one goes protect with key on

Both amps are on the same power and ground. 4ga going to a dist block that Ys the power to the two amps.

With the ignition button pushed, both amps work fine. When i turn the key on one amp goes into protect.

What gives?

Im not sure I fallow whats changing electrically, between ignition button on and then key on.

Boats a 97 ss nautique. When u hit ign it turns on radio and allows power to boat when u turn key on.

So i can play the radio fine with the key off. But when i turn the key on the ONE amp goes protect mode. But it is reading a constant 13v while cycling into protect mode.

Key on turns on gauges and perfect pass. This is all sitting in my garage. Engine isnt running.

Scratch the key on thing. I just turned on nav lights and blower and stuff and it went to protect without key on.

Must be short on power?

Shorts blow fuses, whats the battery voltage?

Voltage on the amp terminals was 13v with the charger running

I'm starting to think this is a defective amp. I just checked fuses on the amp, they are fine. I unhooked the other amp to see if it was robbing the problem amp of power and it wasn't. I don't know what else to do.

Start by disconnecting speaker and RCA connections one at a time to see if it goes back to normal mode.

What is the model of each amp?

The one that is working is a polk d5000.5 and the amp gining me trouble is a polk d2000.2.

Ii have tried unhooking speaker connections and that doesnt fo a thing. I will try pulling rcas later today

If it stays in protect mode will all inputs and outputs unplugged and after a hard reset, then the problem is pretty much internal.

Normally an amp will go into protect mode if it detects a difference in resistance on one of the speaker terminals, aka a blown speaker. That way it won't keep pumping power to it and potentially short itself out if the speaker has improper resistance from blowing.

1: Turn the ignition on, make sure it's not in protect, now turn the key on, or turn the lights on, whatever makes it short normally, and verify it still goes in to protect.
2: Disconnect one pair of speaker wires, repeat step 1.
3: Repeat Step 2 until amp no longer goes into protect mode.
4: Once the pair is found, hook the other speaker wires back up one by one and repeat the check. It should stay out of protect mode.
5: If that didn't work, repeat the process with the RCAs, one plug each time, not one pair each time.
6: If it still goes into protect after all of that, and at this point you would have nothing except power, ground, remote connected, you possibly have a bad amp or some kind of power wiring situation going on where the key/nav lights is causing a short somewhere. You are more likely a bad amp since your other amp is hooked up off the same wires and doesn't go into protect.

I've given up on this amp. The customer service guy at Polk thinks it's defective. I have tried everything above with no success. Gonna cut my losses.


Which amp should I get to solely power a WS pro 485? The speaker likes 500w rms or so I hear. I don't have the budget for WS Amps so leave them out.

Kicker KXM400.2 = 400W rms x 1 @ 4 ohm $330

Kicker IX500.2 = 500W rms x 1 @ 4 ohm - outgoing model

Wet Sounds HT-2 = 585W rms x 1 @ 4 ohm $430

I like the first kicker, after doing a search this amp came up a few times


http://www.woofersetc.com/p-10137-p6...amplifier.aspx

Any good?

The new amp came in today and it is doing the same thing. So i hooked up the polk amp to its own dedicated power and ground straight to the battery and it still goes protect. But i tried unplugging the rca input while it was on its own power and it went off protect mode.

So it seems that the rca input is causing this problem. Because i have two amps i was using a single canle that goes into the small amp and then use the small amps output rca's to go to the big amp. I tried running a Y connection from behind the headunit and give each amp its own dedicated rca cable and that still didnt fix it.

Any other ideas?

Take the working amp out of the loop and give the suspect amp the RCA all to itself and see.

My guess is you have DC voltage traveling down the RCA cable because there is a ground problem somewhere and it is trying to complete the circuit. That would trigger the protection mode.
Remove the HU from the boat harness completely and temporarily get both HU B+/memory and ground from the amplifier primary terminals (not battery). Later, an interrupt relay could be a permanent solution.
Triple check that amplifier's ground and every termination and lug.
Use a ground loop isolator to block DC flow on the RCA shield.

Tried that Mike, no luck....

I put a voltmeter to the RCA's to check for DC voltage and I am not getting any. Positive to the tip, negative to the shield.

The guy a polk said that it is probably an issue with my headunit, Sony DSX-MS60.. I am at a loss.

Originally Posted by DavidAnalog

My guess is you have DC voltage traveling down the RCA cable because there is a ground problem somewhere and it is trying to complete the circuit. That would trigger the protection mode.
Remove the HU from the boat harness completely and temporarily get both HU B+/memory and ground from the amplifier primary terminals (not battery). Later, an interrupt relay could be a permanent solution.
Triple check that amplifier's ground and every termination and lug.
Use a ground loop isolator to block DC flow on the RCA shield.

I will try that when i get a chance tomorrow. Thanks david

no luck as in what? if the suspect amp still went into protect mode while not sharing an RCA with the other amp, and this is the 2nd amp, you have eliminated the existing amp, pointing more toward the head-unit.

Bypass the head-unit as the source unit, with a 3.5MM to RCA right into the amp.

To me it seems like a remote turn on lead problem. Is the remote turn on the same for both amps and also ties in on the same battery that powers them? Example would be if the remote lead comes from the deck does that deck get its power from the same battery that's powering the amps? Try connecting a jumper wire from the positive to the remote turn on and see if you still have the same problem. (Disconnect the original turn on lead first)