Amp protection circuit has been activated - Onkyo TX-SR605 Receiver

The Power Crown XTi 6000 is a power amplifier, and it sounds like it is activating its protection circuit and not generating a Pulse Width Modulation (PWM) signal. There could be a few different reasons for this behavior. Some possible causes include:

• Overheating: The amplifier could be overheating, causing the protection circuit to activate in order to prevent damage.
• Short circuit: There could be a short circuit in the amplifier, causing the protection circuit to activate.
• Input signal issue: The input signal to the amplifier could be causing the protection circuit to activate. This could be due to a problem with the source, such as a malfunctioning mixer or a disconnected cable.
• Output impedance or load mismatch: The amplifier may have a mismatch in output impedance or the load impedance which can cause the protection circuit to activate.
• Firmware or software issue : There could be a problem with the firmware or software that controls the amplifier, causing the protection circuit to activate.

Without more information, it's difficult to say for certain what the problem is. It's recommended to check the manual for troubleshooting steps and also check for any possible firmware updates. If problem persist it's recommended to take professional help.

It will help if you can identify the 40 Amp fuse that is being toasted when the key is turned.

I looked briefly at a fusebox diagram and found 3 circuits protected by a 40 Amp fuse. The Lamp circuit protects several circuits which have smaller rated fuses on each separate wire. The 40 Amp protection seems to be a safeguard if all the smaller circuits are active in total. Turning off the automatic headlights, should reduce power drain.

The next circuit is the Rear window defroster. Can easily pull 40 Amps, but once the 40 Amp fuse breaks, it should have no effect on the engine.

The last circuit, on the cars with Trailer Tow or Police package has a
40 Amp fuse on the Battery charge Relay. This is a remote possibility. But the engine should be able to run without an Alternator for several minutes using Battery power.

Have them check the fuel pressure. The Inertia switch could have tripped while the car was being repaired. It does not explain the wiring short, but can explain the no start condition.

Again, if the same 40 Amp circuit is overloading, identify the circuit with the fuse box diagram.

Hello m_george191,

Usually an amp will go into protection when there is a problem with the wiring, impedance load, or when overheated. Immediately when hooked up, it probably isn't overheating.

Most likely, there's a short or ground on a speaker wire, an input, or a faulty ground to the amp itself. Frayed or broken insulation, stray wires shorting across the terminal blocks, and shorted voice coils can all cause the protection circuit to activate.

First check your power and ground wires. Then disconnect the speakers and inputs and see if the amp powers up normally. If the amp still goes into protection with all wires other than 12V +, Ground, and Remote disconnected, the amp itself is defective. If it powers up normally with all other wires disconnected, reconnect the inputs one at a time to determine if one of them causing the problem. Likewise, reconnect the speaker wires one at a time.

Hope this helps.

Hi, first thing to do is to check the power supply look for a larger capacitor & using voltmeter measure both sides from ground to positive & ground to negative. Next check the speaker protection circuit if active. If not active measure the voltage from ground to the speaker output before the relay of speaker protection device. The voltage should be zero or close to zero volt. If more then the power transistor or power IC is toasted.

sometimes the protection circuit will enable because of a bad speaker i would suggest taking the load off of it by removing the speaker wires and turning it back on. if it stays on take an ohm meter and check the speakers should be between 2-4 ohms load.

Remove all speaker wires from the receiver and turn it on.

If it still goes into protect, I'll bet the house that one of the channels is shorted out and it needs repair. This is a job for a pro.

If it doesn't go into protect, check for a short in the speaker wire or for a bad speaker.

Hello, is this a Radio Shack PA amp or Jamo amp? The unit is probably in "Protect" mode. Is this a PA system or a receiver...receivers have a protection circuit that will not let the speaker relay activate if the amplifier output section is shorted and sending voltage towards the speakers...so they won't fry!!The speaker relay should activate within 3 to 5 seconds if your output section is ok.

barneyluc

Hi
Remove all speakers cables or wires and check all from behind the Receiver. if there are any loose terminals or any metal object in between the terminals.
though it might be a coincidence that you have a problem in the Receiver.
unplug the power cable from the wall socket and remove all cables.

after you remove the cables plug the power cable in the wall socket and try if you see the protection displayed , the receiver needs service.
Good Luck
Regards

I'd be inclined to check to make sure there isn't a short circuit somewhere in the output lines. Maybe a wire is crushed against the car's body or bare wires touching or badly fitted RCA plugs. All of these things could activate the protection circuit. If you have a multimeter it would make life easier but don't forget your speakers will show up as 4 ohms so that's not a short. BMW