aftermarket harness relay

[NoSounds]

hey guys, first post

I got a 2010 gmc sierra, no bose no steering wheel controls just basic am/fm radio.

I will be relacing with a single DIN alpine cd, Bluetooth and Sirius. the after market scosche harness cam with a black relay...is it necessary to wire this in also? thanks

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[fasfocus00 5,000+ posts]

most likely it is. read the instructions b/c the last time I encountered this was with a Metra GMOS-4 on an '07 Vette and only the Vette's required the relay while all the applications didn't require the relay.

 

[NoSounds]

I read the instructions but its a note at the end, I think it may be a relay for a high power unit, but not sure.

 

[CrossoverOre 10+ year member]

generally speaker those modules have a 1 or 2 amp output. they supply the relay for when hooking up more than just the deck to the acc. You dont have to wire it up if just using the deck but its not a bad idea. just kind of preventative maintnance. It should say in the instructions just what kind of output it supplies.

 

[Joebobclark 10+ year member]

That relay is in there incase your vehicle doesnt have a 12v switched source in the factory harness. Alot of vehicles dont anymore. The radio is told to turn off/on through the canbus or other methods. All aftermarket decks require a 12v constant and a 12v switched source, the constant keeps the settings and station presets from being lost at turn off and the switched turns the unit on/off.

I dont know if you need it for your application, but you may... try it without and if the radio stays on after you turn the key off and open the drivers door, you will need to install the relay.