Ampifier protection mode problems

There is something shorting out the amp. What you will need to do is disconect all wires and hook up one at a time. Connect ground, !2 volt and remote see if amp turns on ok. If it does try connecting each speaker seperately to see if either one sends the amp into protect mode. Then connect the rca. See what causes the amp to go into protect mode.

You have a ground fault. Check all ground wires and then make sure the rca cables are not broken in any places. If everything is good there is a ground fault inside the amp.

Disconnect all speaker connections and rca cables. Leave power, ground and remote wires intact. Try turning on again. If you still have a protection light your amp is faulty. . Double check all connections. Good luck.
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check your wiring, is it properly grounded? is your remote positive wired to your ignition's positive line?

your ampifier is in protect mode, try to dettache the speaker and turn on it.if the green ligh on ,one of your speaker is deffective but still the red light on theres something wrong with your amp.

YOU HAVE A SHORT CIRCUIT WITH THE RCA CABLES THAT ARE GOING THO THE SUB WOOFER AMP CHANGE THE RCA CABLES FOR A NEW ONES!! AND IF YOU CAN BUT IT HEAVY DUTY

Hello, I am sorry about your issue. I f the receiver does not stay on with nothing connected it would need to be serviced. Thank you, Onkyo USA

It sounds like your amp is not grounded properly and is tryin to use your radio as a ground through the RCA's or there is a bad channel (dead short) in the amp.

Hi, what you need to do is unplug all the connections to the amp. The amp goes into protection when the circuitry over heats.\
First decrease all your gains to minimal volume.
Connect your 12+V, remote, and ground.
See if the protection light comes on then.
Next plug in your RCA cables.
Check protection light.
Then plug in your subwoofer cables.
See if you are still in protect mode.
Hopefully everything works alright again.
Just slowly increase the gain to see what the cut-off is. Make sure you aren't dropping the ohmage too low on the amplifier. Check manual for correct wiring and such.

You say the protection mode only occurs when you plug the RCA's in. Does it have to be both RCAs or just one?

The other end of the RCA cable is plugged into the HU?

It possible the RCAs have too much DC voltage on them, causing the amp to go into protection.

Is there a short in the RCA cable?

I would definitely check out the RCA connection at the back of the HU, as it sounds like there could be other issues there. Make sure the RCA connectors aren't touching any other metal (especially +12V).