PMU 16 Ground

Quick and easy one if anyone would be kind enough to share.

I'm just curious what size ground wire should be used for the PMU, I presume it will be small but I'm not a fan of guessing... Or starting fires.

Thanks in advance for any help here, unfortunately it isn't in the instruction manual 👍

I'm just gonna use 20AWG.

Pretty sure 22AWG would still be plenty, maybe even 24AWG like the PMU's +12v feed if using an ECUmaster isolator, but I can't gamble with it and in this location there's no real size / space saving benefit.

I'm still interested in hearing from anyone who knows.

I would go a bit bigger, like 18AWG as the ground pin on the PMU uses a bigger terminal and 20AWG don't fit too well in these. But it won't carry big current as it's for the analog or switch input and grounding of the PMU itself.

I actually called ECU masters to ask this question. Yes this pin only sees small current from reference ground for analog inputs. I used 20 AWG on my harness with this pin to accept the small wire.

https://www.mouser.com/ProductDetail/Aptiv-formerly-Delphi/211CC3S1120?qs=HumNWfwekiFIkiIZKzmB3g%3D%3D

That is a 2.8 SICMA pin that will accept a 20 AWG wire. Be cautions that small AWG wire will not have sufficient OD on the insulation to properly seal on that location. This was not a big deal for me since I have a heat shrink boot and epoxy to seal everything but something to considered if you are relying on the connector seal only.

Generally the PMU's ground is just for power on the electronics and for the analog inputs, so it draws very small current.

But there is PDMs with dual half bridge outputs, so a bigger ground wire gauge would be needed.