I used SPR4 to run 12V for the fuel pump mod on my ms2. It's not working when I hook up the MS to my car. I had to jump GDN and FP on the diagnosis box in the engine bay to get the car to start.

I check the wiring on my car and it's fine. I chased all my solder points on the MS, more specifically the fuel pump mod and everything is good, no shorts.

My MS is not pushing out 12v to SPR4. Do I need to make a software change in Tunerstudio to make this work on SPR4?

 

Did you wire 12v to the spr4 internal connection?

 

I used the following circuit.

 

What's wrong with just jumping the wires?

 

What do you mean? Can you clarify?

 

Most of us use the normal fuel pump circuit and send it out to the AFM.

in the AFM connector, you jump that pin to the pin that connects back to the fuel pump relay.


then MS controls the pump like normal without a sketchy circuit you had to build.



This sounds like it's never worked? you probably built the circuit wrong or did something n00bish.

 

@ braineak Noob is right on. It never worked, yet. Funny you say sketchy circuit, I followed your write up:
https://www.miataturbo.net/useful-sa...76/#post169701

So, it sounds like I should do away with this circuit and utilize the existing GND output in the MS to drive the pump through the AFM now.

Can you clarify? I appreciate any feedback. Really I do...

 

jump this




like so:



put normal purple wire fuel pump output (pin 37) on 2O.

 

Thank you Braineak, that helped. Your suggestion was so much easier than building that circuit. I was able to get the fuel pump to turn on as expect. =)

 

Pull ST_SIG fuse, first. otherwise the transistor go boom.

 

what transistor? here's not using one now.

one does not need to pull ST_SIGN fuse if you do build the unit like I do.