PRODUCT DETAILS
Rywire Main Relay Kill Switch & Upgrade Harness - OBD0 / OBD1-OBD2
Got an older Honda or Acura that won't start because the main relay's dead again? The Rywire main relay upgrade harness fixes that problem permanently. It replaces the failure-prone factory Honda relay with a standard automotive relay you can pick up at any parts store for a few bucks. The harness also includes a removable kill switch that cuts power at the relay level, so your car won't start unless the switch is plugged in. No cutting or splicing your factory harness. Just plug it in and you're done.
Why the Factory Relay Fails
If you've owned an older Honda, you already know about the main relay problem. The factory relay sits in the dash where it gets hot, and the solder joints inside crack over time. When it fails, your fuel pump won't prime and the car won't start. You're stranded until you replace it, and a new factory relay costs way more than it should. The Rywire harness swaps the Honda-specific relay for a standard automotive relay. When that relay eventually fails, you're not waiting for a special order part or paying dealer markup. You just grab a new relay from any parts store and swap it in five minutes.
Kill Switch That Actually Works
The harness includes a removable toggle switch that interrupts power to the main relay. No power to the relay means the fuel pump doesn't run and the car won't start. Someone can turn the key all they want, but without that switch plugged in, your car's not going anywhere. You just unplug the switch and take it with you when you park. It's not some hidden toggle under the dash that someone can find if they're determined. They'd need the actual switch to start your car.
Plug It In, You're Done
The harness plugs straight into your factory main relay connector. Unplug the old relay, plug in the Rywire harness, mount the new relay somewhere convenient, and route the kill switch wherever you want it. You're not cutting wires or soldering anything. The whole install's reversible if you ever need to go back to stock.
OBD0 or OBD1/OBD2?
You need to order the right version for your chassis. OBD0 is for pre-1992 Hondas and Acuras. OBD1 is for 1992+ cars, and it also works on OBD2 vehicles. Check your build year and order accordingly.
What You Get
- Rywire main relay upgrade harness
- Standard automotive relay
- Removable kill switch
- Plug-and-play installation
- No cutting or splicing required
Compatible Vehicles
- OBD0: Pre-1992 Honda and Acura vehicles (White Plug Images)
- OBD1/OBD2: 1992+ Honda and Acura vehicles (Red Plug Images)
Note: Keep the kill switch with you when you park. Without it, your car's not starting. Order the OBD0 version for pre-1992 vehicles or OBD1 for 1992+ vehicles. The OBD1 version works on both OBD1 and OBD2 chassis.