Wiring a relay to upfitter switch

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soxfanjake

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I'm installing a 12 volt outlet in the bed to power a Dometic Refrigerator/Freezer. I wired a standard 30/40 relay to the AUX 6 wire as shown in the "POSITIVE TRIGGER" pic. The 86 pin is wired to the AUX 6 wire as the trigger.

My problem is, the 87 pin is now hot when the AUX 6 switch is off, and dead when the AUX 6 switch is on. Obviously the opposite of what I was after. Should I be wiring as if it's a ground trigger like in the 2nd pic?

Thanks in advance for any help.
 

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smurfslayer

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try this relay diagram

30 is battery power
86 is ground/earth
85 is ‘trigger’ aka upfitter
87 goes to the accessory - in your case, the plug.

here’s another link that may explain it more eloquently than I:

"5 pin relays provide 2 pins (85 & 86) to control the coil and 3 pins (30, 87 & 87A) which switch power between two circuits. They have both normally open and normally closed connection pins. When the coil is activated, power will be switched from the normally closed pin to the normally open pin."
 
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soxfanjake

soxfanjake

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try this relay diagram

30 is battery power
86 is ground/earth
85 is ‘trigger’ aka upfitter
87 goes to the accessory - in your case, the plug.

here’s another link that may explain it more eloquently than I:

"5 pin relays provide 2 pins (85 & 86) to control the coil and 3 pins (30, 87 & 87A) which switch power between two circuits. They have both normally open and normally closed connection pins. When the coil is activated, power will be switched from the normally closed pin to the normally open pin."
Thanks so much for the reply. Sucks that neither diagram that came with my relays was correct (also sucks that I have to rely on diagrams because my electrical knowledge is so limited). Some cutting and re-heatshrinking in my future.
 

smurfslayer

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he’s right, you only need a 4 pin. 5 pin can work, but you’ll have an unused post (needing to be insulated or tied/wrapped)
I understood you -had- a 5 pin.
 
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soxfanjake

soxfanjake

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he’s right, you only need a 4 pin. 5 pin can work, but you’ll have an unused post (needing to be insulated or tied/wrapped)
I understood you -had- a 5 pin.
Correct. I have a 5 pin only because I had a whole box of them. I'm just capping the middle pin.
 

downforce137

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its my understanding that the 5 pin relay makes the middle terminal hot when energized.. thats not what is happening here?

sounds like you have a normally on relay and when energized its hot on the middle pin, instead of 87

you need a normally off relay...
 
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soxfanjake

soxfanjake

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try this relay diagram

30 is battery power
86 is ground/earth
85 is ‘trigger’ aka upfitter
87 goes to the accessory - in your case, the plug.

here’s another link that may explain it more eloquently than I:

"5 pin relays provide 2 pins (85 & 86) to control the coil and 3 pins (30, 87 & 87A) which switch power between two circuits. They have both normally open and normally closed connection pins. When the coil is activated, power will be switched from the normally closed pin to the normally open pin."
Smurfslayer for the win! This is the correct wiring for this scenario. It's working now. Next stop, wiring the 5 & 6 switches to be hot with the engine off. Thanks for all the replies and help.
 

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The Car Stereo Company

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its my understanding that the 5 pin relay makes the middle terminal hot when energized.. thats not what is happening here?

sounds like you have a normally on relay and when energized its hot on the middle pin, instead of 87

you need a normally off relay...
87 and 87a (middle pin) is a normally closed circuit. it is a complete circuit until the relay is powered. 87 and 30 is normally open. which means when the relay is powered they connect until power is off
 
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