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WagonCrazy
01-12-2018, 01:43 PM
wiring up the 57 nomad. have power bucket seats out of a lexus .
the fuse panel is mounted to the center trans tunnel, just ahead of the T56 shifter.
is there any reason why i need to wire in a relay to power the seats?
its less than a 3 foot wire run from fuse panel to each seat motor.
can i just wire them both to thru a fuse in the panel and call it a day?

would be wired to 'always hot 12v" so they can be operated with the engine off...

hmmm, i wonder if the electronics under each seat already have relays there? gonna have to check that.

if not, thinking of wiring directly to a 30 amp fuse ...no relay.

problems?

Rocketman
01-12-2018, 08:36 PM
I think if you use a heavy enough wire you will not need a relay. I think I would use a circuit breaker though and make sure it is close to the power source.

Custer55
01-12-2018, 09:03 PM
If I remember correctly I wired mine to direct battery power on a 30 amp breaker with a circuit breaker also. I have not had any issues with it that way but I rarely adjust the seat anyway. I am it's only driver and once I set the seat to my liking it hasn't been moved much anyway.
Brian

WagonCrazy
01-14-2018, 05:07 PM
seems like a wiring a circuit breaker and a fuse inline is redundant?

Rick_L
01-14-2018, 06:44 PM
30A seems like a lot of current for a power seat.

I don't think that power seats usually use relays in their OEM applications.

A review of the wiring diagram for the car your seats came from would be useful, and duplicating what the factory did on that would be good.

chevynut
01-15-2018, 09:10 AM
Adding a relay for seat power would be redundant. Every motor is driven by a relay already, or by a switch made to switch that much current. My driver's seat motors are switched through a memory module with relays inside of it, and the passenger seat switches switch the power to the motors directly. The only question imo is whether you should use a fuse or a breaker. The seat motors shouldn't take anywhere near 30 amps...probably under 10A in normal operation. The fuse is only there to protect the wiring in case something shorts out.

WagonCrazy
01-15-2018, 11:07 AM
Thanks guys.

You know you are losing it when you've gone down this road before, completely forgot about it, then did a google search and found the link IN THIS FORUM where you went all around the issue and back again.

Sheesh...my brain is toast...

http://www.trifivechevys.com/showthread.php/3859-Wiring-up-late-model-power-seats-in-our-tri-5-s

TrifiveRichard
03-11-2018, 07:23 PM
One thing you may want to consider WC is where you are connecting to power. If the power is switched (eg by the ignition switch), you may want to use a relay to limit the current handled by the switch. Dick

chevynut
03-11-2018, 07:55 PM
I'm pretty sure every car I have has the power seats wired hot all the time. I'm going to use a 30A breaker that is fed straight from the battery to power my seats. I already have enough relays as it is :).

Rick_L
03-11-2018, 08:19 PM
Richard, you bring up a point that goes beyond the seats. Cnut is correct that most OEM seats are wired hot to the battery though.

It's a good idea to use a relay to power all the "key on" functions. It reduces electrical load on the ignition switch. This includes EFI functions if you have that.