A sudden loss of power to your stereo receiver is a potentially serious problem, even if it only happens intermittently. You must identify the cause of the problem and fix it quickly to avoid damaging your equipment.
check the connections
It’s always good practice to make sure your equipment is turned off before you start poking around and testing connections. Check that there are no loose strands of speaker cable touching the rear panel of the receiver or the back of connected speakers. Even a single strand of speaker wire is enough for the receiver to shut down, due to a short circuit. Remove any loose wires, strip the affected speaker wires with the wire strippers, and reconnect the speakers to the receiver.
Inspect the speaker cables for damage or fraying
If you have pets, check the total length of all speaker cables to make sure none have been chewed on. Unless you have cords hidden or out of the way, appliances (for example, your vacuum), furniture, or foot traffic also damage cords. If you find damaged sections, splice in new speaker cable or replace the whole thing. When you’re done, reconnect the speakers to the receiver. Check for a solid speaker wire connection before turning anything back on.
Evaluate overheating
Most electronic components have a built-in safety mechanism to protect against overheating. These safety systems are designed to automatically shut down the device before the heat level causes permanent damage to the circuitry. Very often, the device will not be able to turn back on until the excess heat has sufficiently dissipated. Check if your receiver is overheating by placing your hand on the top and sides of the unit. If it feels uncomfortably or unevenly hot to the touch, overheating is likely the cause. You can also check the receiver’s front panel display, as some systems have warning indicators.
Check speaker impedance
Low impedance means that one or more speakers are not fully compatible with the power supplied by the receiver. A speaker with an impedance of 4 ohms or less may be too low for the receiver you have. The best way to confirm proper impedance levels is to check the speaker and receiver manuals for compatibility.
Ensure adequate ventilation
It’s important for a stereo receiver to have adequate ventilation, especially if it’s located in an entertainment center or near other electronics. It is best not to have anything on top of the receiver or to block the vents or exhaust because the blockage traps heat and leads to overheating. Move the receiver so that it is away from other components, preferably in a cabinet that is less confined for better airflow. You can also install a small fan inside the entertainment center to increase air circulation.
Avoid direct sunlight
Protect the receiver from sunlight. Sometimes this solution can be as simple as closing the blinds. If not, you’ll want to relocate your receiver so it’s out of the way.
Wipe off excess powder
Even a thin layer of dust acts as an insulator. Inspect the inside of the receiver through any open vents or slots. If you can see any dust, use a can of compressed air to blow it all out. A small handheld vacuum can help suck up the dust so it doesn’t relocate elsewhere.
Check Current
Underpowered circuits are at risk of damage. If a receiver doesn’t get enough power, it will turn itself off. If your receiver shares a power outlet with another high-current appliance (for example, a refrigerator, air conditioner, heater, or vacuum cleaner), the receiver may turn itself off when there is not enough current. Or if the receiver is plugged into a power strip, there may be too many electronics plugged into that same power strip. Plug the receiver into a wall outlet that is not used by anyone else.
Serve the receiver
If faulty cables, overheating, or low current are not the issues that are causing the receiver to shut down, then the unit likely needs service.