Best 12v Ign source under hood for e-fan.

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MrPink

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Alright guys as the title states I am looking for the best place to pull 12v ign power for my e-fan. I was thinking the Fuel Pump Relay, but is there any other spot that would be better?

Edit: It does have a relay setup I am looking for key-on power for the relay setup.
 
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PlayingWithTBI

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How about installing a dedicated relay (fused directly from the battery), switched off the ignition, which supplies power to your e-fan relay?
 

0xDEADBEEF

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What he said, as far as the power source. You want the fan on all the time?
 

MrPink

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How about installing a dedicated relay (fused directly from the battery), switched off the ignition, which supplies power to your e-fan relay?

What he said, as far as the power source. You want the fan on all the time?


I should have stated it has a relay setup wired in I am just looking for key on power for the relay setup.
 

PlayingWithTBI

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I should have stated it has a relay setup wired in I am just looking for key on power for the relay setup.
Yes, and that's why I suggested using a dedicated relay so you have full battery voltage to your setup. I probably wasn't real clear on my thinking?
 

MrPink

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Yes, and that's why I suggested using a dedicated relay so you have full battery voltage to your setup. I probably wasn't real clear on my thinking?


It has both a 12v key-on and a dedicated 12v. In my relay setup I have the dedicated 12v going to AUX-A on the block asm which I have confirmed is 12v hot w/o key on. I am wondering if the Aux-B stud is key on hot though as it showed nothing when I multi-metered it with key off.
 

GMCTruck

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Your signature says 1995 truck. Some, if not all of these trucks are pre-wired for an auxiliary battery relay which would be located along the drivers side inside fender very close to the fuse box. There is a switched 12V ign wire and a ground wire taped up and tucked down by the main wiring harness. The wires are terminated with a quick connect type connector. I can't remember which fuse controls it but it says TP2 relay as well as several other circuits.


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TechNova

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a fused wire to battery is best. You can also a 2/0 cable from the battery and use your own terminal block. this makes it handy if you need to add a few circuits. Make sure to fuse properly. I have added power and ground terminal blocks to firewalls on cars. You can do single post or a small fuse block.
If you have a side terminal battery, be careful how much you hang on it. The threads in the battery are lead and can wear or strip out from the weight of multiple wire bouncing as you drive. I did my own big 5 update with multi strand copper cable and noticed it was much heavier than the factory cable. I try to support it so only a small amount of the cable is supported by the battery terminal.
 

GMCTruck

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I will just add , those wires in my above post are for the relay coil. Not to get power for the fans.
 
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