Relay Question

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Relay Question

Postby paul_faraianu - May 3rd, 2021, 9:25 pm


I have a 2010 Mariner 2.5L 4WD Base. ught
I want to install a Relay that will turn on power to: CURT 56329 Vehicle-Side Custom 4-Pin Trailer Wiring Harness, Dash Camera, GPS and Break Controller.
I taught of using a Relay that will only turn on the 4 Accessories only when the car is running. So pretty much instead of having a On Off Switch that i can turn on and of, I would like the Relay to turn on in the RUN position.
Thank you
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Re: Relay Question

Postby tomw - May 4th, 2021, 12:49 pm

Not sure about 2010, but the 07 model has a switched power outlet(cigar lighter socket) that is hot with the key ON. That 'hot' could be used as the control signal for a separately powered relay for whatever gizmos you want to power with key ON.
Using the switched power as control, you would tap some always hot, WITH A FUSED conductor, to send power to the power in portion of the relay, and connect the load to the switched connection.
I would want to fuse the load side also.
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Re: Relay Question

Postby bangster - May 4th, 2021, 3:25 pm

I see no reason to use a relay, only questionable thing would be a brake controller and I think they will have the logic inside, so you would have a higher amp required always powered from battery supply, and a switched one. I personally would first try to find an unused but hooked up circuit in the fuse box, or a used switched one, and use a fuse tap.

For my trailer lights (no brake controller) I tapped into unused circuit (in my case, in the rear compartment fuse box, so running 2 feet of wire and not 15 feet), for my dash cam I tapped into a constant power (for memory, power, and optionally setting up motion detection) and switched, all using fuse taps. I had plenty to choose from, and I looked at the up stream fused item under the hood to be sure I wasn't going over that limit, but each circuit (the original and the added on one) are fused separately).
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Re: Relay Question

Postby ProjectSHO89 - May 4th, 2021, 4:45 pm

Not sure about 2010, but the 07 model has a switched power outlet(cigar lighter socket) that is hot with the key ON.
Nope. Both are ALWAYS HOT on the 2010.

The 2008-2012 have essentially three power buses:


It does not have any "HOT in RUN-only" power feeds. You'd have to hand-engineer that in order to activate a relay (or other load) in RUN-only.
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