Hybrid fuel pump wiring

just plain john

El Camino a Go-Go!
Joined
Feb 24, 2007
There is no factory fuel pump circuit in my hybrid build so I need to add one. I plan to run a hot and a ground down the framerail direct from the battery. Underhood I have the factory engine harness with the fuel pump relay. I want to utilize the control circuit from the factory relay to switch another relay I will mount near the tank somewhere and bypass the factory relay. Is this plan workable? It should give me full battery voltage directly to the pump. Opinions?
 
Operationally maybe, but not really a hotwire kit. I purchased a hotwire kit but with no fuel pump circuit to begin with it's useless. I've never done anything like this before, and the only support I'm getting comes from this board. I'm thinking a sealed 30 amp relay and #10 wire direct to the pump, and I need to identify the control wire that triggers the factory relay, which i will extend to the framerail mounted sealed relay. Should work, shouldn't it?
 
Yes, that will work although I would eliminate the original fp relay and run the signal wire direct the the relay on the frame rail. No need to double relay.

Use the hot wire kit and mod it for your application.
 
Thanks Rick, I thought so. While I'm at it, what signals the relay? The pump is supposed to run at key on, but if the car is not started it shuts off. Is that right? Is there a pressure switch somewhere or what?
 
No problem, glad to help. That is how it works. The ecm controls the signal. All you have to do is get the grn/blk wire back to the new relay.

Here is ecm pinout. ECM Connectors
 
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