"CHECK SP WIRES" is the Yamaha telling you exactly what's wrong: it sensed a short on the speaker outputs and dropped into protect mode (often shutting down after a few seconds) to avoid damaging the amp. The cause is almost always a stray strand of speaker wire bridging the +/- terminals — so the fix is at the speaker connections, not inside the receiver.
Find the short
- Unplug the receiver and inspect every speaker terminal closely. A few loose copper strands touching the opposite terminal — or two posts — is all it takes. Re-strip each wire, twist the strands tight, and make sure no stray hair of copper bridges anything. Banana plugs prevent this entirely.
- Test by disconnecting all speakers. Remove every speaker wire, then power on with nothing connected. If "CHECK SP WIRES" clears and it stays on, the fault is in a speaker cable or speaker — reconnect them one at a time until the message returns, and you've found the culprit. If it still trips bare, the fault is internal.
- Check impedance. Speakers below the receiver's rating (most Yamahas want 6–8Ω; some let you set a 4Ω/low-impedance mode in the menu) overdraw the amp. Don't parallel two speakers on one channel unless the combined impedance is safe.
If it trips with no speakers connected
That points at an internal fault, but rule out a latch first:
- Power-cycle fully — unplug for at least 30 seconds (a minute is better) to clear a transient protect state. If it then won't power back up at all, that's a won't-turn-on power-state issue, not a wire short.
- Factory reset per your model (often holding STRAIGHT or a front button while powering on).
If it still shows CHECK SP WIRES with nothing attached and after a reset, that's a hardware repair.
Don't overlook heat
If it runs fine and only trips after a while (not a wire short), it may be overheating: move it out of a closed cabinet, dust the top vents, and let it fully cool. A hot, boxed-in receiver throttles and can mimic a protect fault.
FAQ
What does CHECK SP WIRES mean? The Yamaha detected a speaker-output short and went into protect mode. Usually a stray speaker-wire strand bridging the terminals.
How do I find which speaker? Disconnect all of them and power on. If it stays on, reconnect one at a time until the message returns — that cable or speaker is the short.
It trips even with no speakers connected. That's an internal fault. Power-cycle (unplug 30+ seconds) and factory reset; if it still trips bare, it needs service.
Can low-impedance speakers cause it? Yes — speakers below the receiver's rating overdraw the amp. Check impedance, set the receiver's low-impedance mode if available, and don't parallel speakers unsafely.
What about the other messages my Yamaha shows? The Yamaha receiver error messages reference covers no-signal, network, and no-sound messages alongside this one.