FixableUnknown

iTrader: (8)

I am doing the fuel pump rewire mod and have a question about relays. I have an optima trunk mounted battery and a coolingmist AI trunk mount. I plan on using a Bosch type relay for each system. Can I use the stock wire going to the fuel pump to trigger both relays (1 for fuel and 1 for AI)? Will this draw too much current on the stock wire? I know the current draw on the relays are low but not sure how low.

evot23

iTrader: (17)

You'd have to find draw from the electrical manual specs and reference that with the gauge of the wire. I think you'll be fine as that wire should have enough capacity to handle the draw adn the relays will be fine.

mad_7tist

using the stock fp wiring as a trigger would be fine as the pump itself pulls over 8 amps.

arghx

iTrader: (3)

all the trigger does is power a coil inside the relay to close the circuit between terminals 87 and 30 (on a 4 pin relay). i bet it only pulls a few milliamps.

Dudemaaanownsanrx7

iTrader: (23)

+1.
You'll be fine, the stock pump pulls way more then a couple relays will.

FixableUnknown

iTrader: (8)

Thanks for the info guys.

RotaryBuddha

iTrader: (4)

You can use the stock wires to turn on the relay. Will not hurt a thing.

https://www.rx7club.com/3rd-generation-specific-1993-2002-16/fuel-pump-rewire-drawing-773489/


Also your "coolingmist AI trunk mount" don't most of these come with some sort of boost switch/relay so that the pump isn't running all the time.

FixableUnknown

iTrader: (8)

Yes, the AI system has a boost switch. But I don't know if its a switch or a relay, I have not looked at the diagram to see how it works. If it works like a 4 pin relay, then I could eliminate the need for one of my relays. If it is a simple 2pin that doesn't shed the load off the input signal, then I am back to the 2 relays. Ill look at it and let you know how it is setup.