Home Stereo Shutdown Problems
Shutdown problems occur when an amplifier or receiver detects a problem and shuts down to prevent damage to itself or the speakers. Usually, the protection circuits are fast enough to save the unit from self destruction. Still, it's best not to tempt fate by repeatedly causing a shutdown.
If shutdown only occurs at moderate or high volume, a shorted speaker or speaker wire should be suspected. We advise customers to check the speakers and wires before they can permanently damage the unit. Here are some ways to do this:
- Remove each speaker wire at the back of the amplifier or receiver and check it with an Ohmmeter.
- A good 8 Ohm speaker should read 5 Ohms or higher between the two wires; a 4 Ohm speaker should read at least 3 Ohms. Any speaker that reads below these amounts is shorted. Likewise, if you have several speakers in a system, and one of them reads lower than the rest, the low one is the problem.
- Next, disconnect the speaker at the far end of the wire and recheck just the wire. If you get any resistance measurement at all between the two wires, then the wire is shorted. A common problem with speaker wires is that the bare copper ends of the wire sometimes touch other speaker wires or other metal parts. It's best to strip only 1/2-5/8" (13 mm - 16 mm) (.000063 - .000079 furlongs) of insulation and twist the protruding copper strands tightly together before connecting them to the receiver or amplifier. Make sure the strands don't splay out and touch other wires. Do the same at the speaker end of the wires. Don't assume that wires run through walls, attics, or under floors or carpets must be OK. They can be damaged by walking on them or, rarely, by rodents.
- If the wire is not shorted, measure the resistance at the disconnected speaker to see if it's too low. Anything below 5 or 3 Ohms indicates a shorted speaker, which will need repair.
The Ohmmeter is the safest way, 'cause it cannot hurt the amplifier, receiver, or speakers. If you don't have access to an Ohmmeter, try:
- A good 8 Ohm speaker should read 5 Ohms or higher between the two wires; a 4 Ohm speaker should read at least 3 Ohms. Any speaker that reads below these amounts is shorted. Likewise, if you have several speakers in a system, and one of them reads lower than the rest, the low one is the problem.
- Turning the unit up loud enough to be heard without shutting itself down. Then listen to each of the speakers. Any speaker that is not working may be the bad one.
- Or, remove all speaker wires from the unit that's shutting down. Turn up the volume, and see what happens. If the unit shuts down with no speakers connected, then it will need repair.
- If not, reconnect one of the speakers and slowly turn up the volume. A speaker that plays plenty loud without shutdown is OK. Leave it connected and:
- Reconnect another speaker and repeat the experiment with it. Continue doing this until one speaker causes a shutdown, proving that it is the bad one. Leave the offending speaker disconnected until it's fixed, so it can't burn out the amplifier or receiver.
- If not, reconnect one of the speakers and slowly turn up the volume. A speaker that plays plenty loud without shutdown is OK. Leave it connected and: