Remote turn-on wiring plays a small but critical role in every car audio system. This wire signals your amplifier to turn on when the head unit powers up—keeping your audio system efficient and avoiding battery drain. Whether you’re wiring a single amp or learning how to wire multiple amps in your car, remote turn-on wiring is essential to get right.
At Audiomotive, we’ve helped car owners throughout San Leandro, San Lorenzo, Fremont, and San Francisco build clean, professional audio systems. Here’s what you need to know about remote turn-on wiring.
What Is a Remote Turn-On Wire?
The remote turn-on wire carries a small 12V signal from your head unit to your amplifier. This low-current signal tells your amp when to power up and shut down. Without it, your amplifier may stay on even when your car is off, which can quickly drain your battery.
Most aftermarket stereos have a blue or blue-with-white-stripe wire labeled “REM” or “Amp Turn-On.” This wire connects directly to the amp’s remote input terminal, completing the on/off trigger system.
How to Connect a Remote Turn-On Wire
Connecting the remote turn-on wire is simple but crucial for system performance:
- Locate the remote output wire from your head unit (usually blue or blue/white).
- Run a 16- to 18-gauge wire from the stereo to your amplifier.
- Connect the wire to the amplifier’s REM or Remote terminal.
- Secure the wire along your signal or power cable path to prevent pinching.
For a single amp, this process is quick. But when installing multiple amps, you’ll need a few extra steps to split the signal properly.
Remote Wiring for Multiple Amplifiers
When wiring more than one amp, the remote wire from your head unit needs to split and run to each amp’s remote terminal. You can do this by:
- Using wire splitters or a terminal block to divide the remote wire.
- Daisy-chaining the remote terminals, connecting from one amp to the next.
- Using a relay if your system has three or more amps to ensure steady voltage.
If you’re unsure about the power demand, or your amps don’t turn on consistently, adding a relay can solve voltage drop issues and protect your head unit.
For clean multi-amp installs, Audiomotive offers professional car audio installation that ensures every wire is properly routed and protected.
FAQs – Remote Turn-On Wiring
Can I use the power antenna wire for amp turn-on?
You can, but it’s not ideal. The power antenna wire usually only powers up when the radio is selected, so your amp may not work with Bluetooth or AUX modes.
What happens if I don’t use a remote turn-on wire?
Your amp may stay powered 24/7, draining your battery or damaging the equipment. The remote wire prevents this by syncing power with your stereo.
Do I need a relay for remote turn-on?
If you’re wiring more than two amps, yes. A relay helps distribute consistent voltage and avoids overload on the head unit’s remote output.
Trust Audiomotive for Safe, Reliable Amp Installs
Getting your remote turn-on wiring right means your amps work when they should—and stay off when they shouldn’t. Whether you’re adding one amp or wiring a full system, Audiomotive has the experience to get it done right.
We proudly serve San Leandro, San Lorenzo, Fremont, and San Francisco with expert-level car audio services.
Need help with your wiring? Contact us today to book a custom install.