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fuel pump speed control in M130

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Hi guys,

I plan to control the speed of an Aeromotive A1000 fuelpump with M130, found out now that this is possible with a DHB. Are there also other ways, or is this the only one? Does anyone have instructions how to tune this in relation with rpm?

What firmware package (and version) are you using? The firmware will need a mechanism for controlling the HB Output with a table that can have RPM as an axis. What is the maximum current draw of the Aeromotive A1000?

The GPR package v1.07.005 Feb 2016 base (and later version, current is v1.10.0042), has a Fuel Pump control which uses a PID loop to control the duty cycle of the fuel pump to maintain fuel pressure. Start with setting a resource for Fuel Pressure Control Pump Output Resource.

Hi David,

the fuel pump draws 14 amps at 60psi. I use Y1B Yamaha FX FZ basemap, which is for a jetski and it´s published from Motec in March 2010.


The M1 ECU Hardware documentation states that there is a maximum 12A current for the low-side HB Outputs. The External Dual Half Bridge (which you referred to in your original post), is rated for 20A continuous duty, so it looks like it could drive your pump.

I don't see that 2010 Yamaha FX firmware package on moteconline, so I can't look at it to see how you might configure a fuel pump PWM. Sorry I can't help more.

Hi David,

the firmware version I have is 01.01.0010, attached the basemap that I used for my tune

and firmware package is :


Yamaha SVHO Stock 98 AUS Octane

Attached Files
  • 1C-Yamaha-FX-FZ-FP-Std-SC-Std-C1-C3-B1-Oct-95-USA-98-AU-EU-29Mar010-v2.e35
  • Attachments may only be downloaded by paid Gold members. Read more about becoming a Gold member here.

Arggghhh... I typed a big long response that disappeared. I'm going to try a different approach. Here is a video showing how to setup your firmware to control an Auxiliary Output that varies the duty cycle based on Engine Speed (RPM).

I would wire the Auxiliary Output Resource to the Dual Half Bridge (DHB), and use the existing Fuel Pump Relay Output to power the DHB. That way you would still have the fuel pump logic to turn on/off the pump, but the Aux Output would control the speed of the pump.

very very helpful explanation, thanks a lot David

How do you control the priming when using the aux output?

I set the duty cycle to 100% when the engine RPM was zero. That's why I suggested he continue to use the Fuel Pump Relay output to enable/disable the fuel pump, just count on the Aux Output to control the speed.

Hi David,

made all adjustments and setups like you said, see wiring diagram and screenshot of M1 software attached. The system works so far but I cannot adjust the speed of the pump. If I set the speed to 0 at an rpm of 0, the pump still runs and also if I choose different percentages, the pump runs all times the same speed. About the frequency of the dutycycle, I have no idea if this could be the problem, maybe it needs to be much higher in kHZ range?

Attached Files

My guess is the aux output isn't activated at all, and you have the polarity inverted -- so it runs at 100% all the time. I believe the output has not been activated because your Inlet Manifold Pressure is above the maximum.

Try the following:

- Change the Auxiliary Output 1 Polarity to Inverting. -- verify that the pump is now off all the time (even when the relay switches the other pump on).

- Change the Auxiliary Output 1 Activate Inlet Manifold Pressure Maximum to something you won't see (400 kpa?). -- now test for operation by setting Fuel Pump Mode to Test, then vary the Auxiliary Output 1 Duty Cycle at 0 RPM. You can certainly play with the Auxiliary Output 1 Pulse Width Modulation Frequency to see if that makes the pump operation smoother, or allows a wider operating range.

If that doesn't get you anywhere -- I would be either getting an oscilloscope, or consider connecting an unused UDIG up to the aux output (or DHB Output) and using M1 Tune ->Online->Capture Inputs... to look at the signals. (I don't know if that would work, perhaps the M1 doesn't drive the aux outputs when capturing inputs, but it's worth a try...)

Good Luck!

Hi David,

got it running perfect. After I set the Manifold Pressure Maximum and changed the Polarity to Inverting it worked.

Thanks a lot for your help !!!

Glad to hear it working. What frequency did you end up using?

200 Hz, see attached picture with all adjustments

Attached Files

Hi David,

got now a problem with the DHB, after short time fuelpump dind´t work anymore and DHB was getting very hot, it seems now that the DHB is broken, cause we have now on exit 1 permanent 4 volts and on exit 2 permanent 0 volts. If we connect fuelpump direct to batterie it runs fine, so DHB is the problem.

Do you have an idea what could cause the damage?

Perhaps the DHB wasn't wired such that it could supply the rated 20A continuous current? Or perhaps your pump shorted, and was drawing more than 20A. Did you have a 20A fuse or circuit breaker?

I would contact MoTeC for support. Start with the German Importer:

Distributor for Germany, Austria and Switzerland

Werner Brückle

Bullreuth 1

D82544 Egling

Phone: +49 8176 999 4870

Fax: +49 8176 999 4871

Mobile: +49 172 811 2053


can someone help me for fuel pump from fuel lab brushless intank 1800 hp pump it have a build in controller pwm 500hz to 1500 hz I am using a custom firmware for m150 for my honda civic Type R by vittuned and I don't have DHB