MoTeC Global Forum

Is it ok to locally ground items such as fuel pump and other 12v devices ? Or should a seperate ground wire be run all the way back and star pointed?

Also, this may be a dumb question but I have a few devices (flex fuel sensor, etc) what are asking for 12v power instead of 5 or 8v.. Where should I pull this when using a PDM? I was thinking all of my 12v supply would be coming out of that, but I am not sure where to pull this 12v for low current sensors. I still plan on using a key, would it be bad practice to pull from the switched side of the ignition switch (using this to trigger the PDM / ECU)

You can use a good local chassis ground for high-current devices like pumps, fans and lights, but I normally provide a separate ground that I know is sized appropriately for the current requirement.

Regarding 12V sensors - since you want the sensor to function when the ECU is on, I usually splice into the ECU power for these sensors (including wheelspeeds, flex fuel, some pressure sensors).

Ok. Thank you for the quick reply. Sounds like I may be on the right track at least. I am just welding a few studs around the chassis to ground these devices so I believe that should be a good solid ground point.

I am retaining the factory lights which also just ground locally..

Thanks again for the help