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Ecu grounding ems em80

Practical Harness Construction - Club Level

Discussion and questions related to the course Practical Harness Construction - Club Level

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Hello guys,

Approaching install of my freshly built harness for my rb25 powered r32 running and ems em80 computer. Just wanted to confirm if anyone can explain how the grounding should be done based on the attached picture. Currently the earths from the sensors run back to the ecu pins g2,g3,h2 (i had an old standard harness running a patch harness to the ecu which worked and i tested the pins to original plugs). My question is I have earth pin h3 to the block as it was the only one that did not have anything going to it and on the diagram it states to run a big black earth to block and small earths to sensor grounds. The ecu uses earths to switch fans, pumps, sensors on and off so have i done the right thing? I want to try plug in this week so an answer asap would be awesome. Any more details required please let me know

Attached Files

I haven't dealt with the EMS80 before and the diagram you've posted is a little ambiguous. Are G2,G3,H2 and H3 4 separate pins at the ECU header? If so I'd normally expect two to be used for sensor grounds and the other two for power grounds. The power grounds are typically heavier gauge wire since the sensor grounds have very little current flow to support. I'm not quite sure how to advise from here though based on your diagram that you've posted.