Geo Metro Fuel Pump Circuit
 

Hey everyone,

If you didn't already know, I am converting a Geo Metro to be a battery electric vehilce (EV for short).

There are a few things I am trying to figure out about turning circuits on and off using the existing things in the car to power new things.

One thing I am not going to use any more is the fuel pump. So it seems to make sense to use the fuel pump 12V power to operate something else, such as an ON/OFF for the electric motor controller with it.

Here's my question - does the fuel pump run all the time the key is in the run position? If so, I can turn the car on and off using that circuit.

If not, tell me why (just so I can learn about this stuff for next time I need to fix a fuel related thing!)

Is there anything else in the car that you think might be helpful for re-purposing for an electric car?

Thanks,

-Ben

The fuel pump relay uses a signal from the ECM to power up and stays on continuos any time the key is in the run position and the engine is running.
You could probably use that relay witha little creative wiring.
I will pull the schematics and see what needs to be bat or ground to keep it energized.
I need to go and look up your year model and such.
I'll post it back here tonight.

The car is a '96 and had the 3-cylinder engine, 5 speed manual transmission.

I guess that's a big part of what I was wondering about is the whole ECM thing. There is no engine in the car, so the car computer will be useless/non-functional.

heres an idea
 

You wanted to use the fuel pump relay.
Good relay, carries full voltage at load, continuous.
BUT
Powered by another relay,
That is
Powered by another relay.
So lets use the first relay in the series.
In the relay box,
In the front left of the engine compartment,
Is a relay called, (your gonna love this)
the
Duh duh duh
Main Relay.
catchy , huh?
4 pins on the bottom.
pins 1 @ 4 have a white wire with a red stripe on it that comes in from the battery on fuse #F1 in the fuse box in the engine compartment. Battery power direct at all times.
pin 2 has a blue wire with a black stripe, this is the control to the relay. Ground this wire and relay energizes. Could be hooked to any kind of switch. Carries almost no current, no worry of arcing.
pin 3 has a white wire with a blue stripe. This is the functional wire from the relay. You could use it to send battery power any where you want.

If you still want to use the fuel pump relay let me know and I will put those in here as well.
You do not need to use the wiring as it came from the factory. You could re-purpose any relay for what you need.
I just found it humorous that they used one relay to power a relay to power a relay.
PM me and give me you mailing address (snail mail) and I will send you the schematics for the car. I have the ones for these relays printed already and it would only take a few minutes to print all the wiring for your ride.
Schultz

Hey Schultz,

Thanks for the info.

The "Main Relay" that you are referring to is in the "relay box" under the hood, right? That's what you are talking about?

Is that Main Relay always on whenever the key is in the on position?

No, it is only on (energized ) when the computer tells it to be.
You have no computer (do you?) so that is useless at this time.
You will need to wire the relays so they work as you want them to.
The "Main Relay" feeds power to the ISCA (idle speed control assembly)relay then to the Fuel Pump relay,
Ooh what a sequence.
Power comes from the bat to the main then to the others.
wait till you see the schematics, then you'll understand.
I am working with the belief that you pulled the computer and so you can just use relays as you wish in the car.
S.

Yes, it is in the relay box under the hood.
(I forgot that question)

Interesting Conversion
 

Hey Ben,
How is the Metro running after the conversion? I'm interested in doing the same to my Metro (someday ...), so if you could share any lessons and hints, I'd certainly appreciate it, and maybe there are others, too.

-liner

Bens saga is chronicled in his thread in the Fossil Fuel Free section. It's a great read.

Another good one is Paul's VERY entertaining thread that records his VW bug conversion.

And of course there's the grandaddy-electric-Metro-conversion-thread, Project Forkenswift.

I've never even ridden in an EV, but I'm sure I could convert a Metro to electric in my sleep after reading these guy's threads! They're great!

Metro Schults, I am trying to get my metro running and the fuel pump is not getting power, could I talk you into sending me those wiring schems/diagrams? I did not realize there were multiple relays before the fuel pump. I have checked fuses, but still no power getting back there. Thanks for any help