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installing aftermarket gauges - always hot or switched

i'm getting ready to do my pillar gauges. instructions said to put the power coming off of a switched 12v power supply (hot when key is on).

would it be too big of a draw to hook them up to a constant power supply? not the lights in the gauge, just the part that moves the needles.

it wouldn't be a huge advantage to have them be "always" on, but if you guys don't think its a problem, i just assume wire it that way.
 

d-kuzmen

Master Ford Tech
2,109
79
Connecticut
I would rather hook it to switched power just incase you see smoke or somthing you can always kill the power to them. Anything hooked to power all the time can/could pull a draw not that it would be large but still i'd feel better switching it.
 

Skandocious

Post Whores Make Me Sick
19,076
655
California
Tom what gauges do you have? Water temp, oil pressure, and trans temp? I can't imagine you'd need to read any of those with the truck shut off (oil pressure wouldn't even show a reading)... And even if you did, you can just turn the key into the ON position (truck still not running). I'd definitely wire it to switched 12v, no question.
 
alright - there's not a ton of benefit from leaving them on all the time...i just kinda like how my wife's car the temp/gas gauge still show a reading with the car off.
 

Skandocious

Post Whores Make Me Sick
19,076
655
California
Who knows how much power they pull... With all three getting power you could go on vacation for 1-2 weeks and come back to a dead truck. Just ain't worth it if you ask me.

If you're REALLY ambitious... You could put them all on a big relay and wire a switch to it :D Flip a switch on your dash to send power to the gauges. That would actually be sorta truck, if you wired the lights up to the switch and everything :) If you wanna go that route let me know and I can draw up a diagram for you.
 

6L PWR

Kansas Chapter member
Who knows how much power they pull... With all three getting power you could go on vacation for 1-2 weeks and come back to a dead truck. Just ain't worth it if you ask me.

If you're REALLY ambitious... You could put them all on a big relay and wire a switch to it :D Flip a switch on your dash to send power to the gauges. That would actually be sorta truck, if you wired the lights up to the switch and everything :) If you wanna go that route let me know and I can draw up a diagram for you.
My Nexus gauges all work with a switch. That way, at night, when I come upon another diesel runnin on the road, I can switch them off until I need to see some readings. It's STEALTH mode. :)
 
3,121
67
Michigan
When i installed the pods on my dads truck, Different from what you might have but this is how i wired em... The trans temp had a one wire if i remember correctly that went to the back of the guage, then the hot and ground for the lights, the pyro was a one wire that went to a thermocouple, and same with the lights power and ground, and the Boost was just a straw like line sorta like an oil pressure guage, and a power and ground for lights.

What i did was hook all the powers together and made a harness, hooked all the grounds together so in turn i had only one wire for power and one wire for ground, so far so goood... But then i took out the light switch and found the wire that had power when the running lights, and the main lights would come on. I figured if you need your lights on outside of the truck, the guages shoudl be lit as well..

To find the power wire i used a test light and probed around and whatever wire made the light turn on i used. Ground i found a spot for that behind the kick panel. Man i cant wait to get my gauges and hook em up. It was fun!
 

Skandocious

Post Whores Make Me Sick
19,076
655
California
When i installed the pods on my dads truck, Different from what you might have but this is how i wired em... The trans temp had a one wire if i remember correctly that went to the back of the guage, then the hot and ground for the lights, the pyro was a one wire that went to a thermocouple, and same with the lights power and ground, and the Boost was just a straw like line sorta like an oil pressure guage, and a power and ground for lights.

What i did was hook all the powers together and made a harness, hooked all the grounds together so in turn i had only one wire for power and one wire for ground, so far so goood... But then i took out the light switch and found the wire that had power when the running lights, and the main lights would come on. I figured if you need your lights on outside of the truck, the guages shoudl be lit as well..

To find the power wire i used a test light and probed around and whatever wire made the light turn on i used. Ground i found a spot for that behind the kick panel. Man i cant wait to get my gauges and hook em up. It was fun!
I've got a similar setup. I tapped my trans temp power into the fuse that powers my gauge cluster so it lights up with the cluster (and thus the headlights). It's also cool cuz it dims my trans temp gauge when I use the dimmer knob for the cluster.
 
3,121
67
Michigan
Yes with my dads truck it also dims, i remember finding that wire that did that and it acually dimmed my test light, and it switch the lights on for the guages, so it was a win win.
 
yea i was planning on hooking the up to the dimmer - can any of you guys get me close to that wire?
 
3,121
67
Michigan
Errrr. i forgot lol... your gonna have to take that switch out and find it with a test light. I wired em on a superduty and they are way different with our trucks..
 

Skandocious

Post Whores Make Me Sick
19,076
655
California
Tom if I remember right, for the power to the lights in the gauges I just tapped into the fuse on the interior fuse panel that powers the gauge cluster. Pull off your fuse panel cover and find which fuse sends power to the gauges. If you've got a test like, do as Mike did and throw a test light on it then turn the lights on and screw the dimmer up and down, see if the test light changes brightness. That should do it for ya YelloThumbUp
 
Yes...wired switched is the way to go. You can turn the switch to the first notch and they are on. Mine are wired into the dash lights. Not sure if I have a dimmer switch. Hmm...did they have them in 56?
 

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