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Multiple Aux outputs faulting


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I'm scratching my head at some new behavior I've hit.  Hopefully more experienced eyes will see something!

When I activate the Aux output for my fuel pump relay (Aux 1), a bunch of the other Aux outputs go to the Fault state.  When I deactivate the Aux 1, the other Aux outputs go back to Active or Inactive as expected.  I can activate other Aux outputs normally.

The fuel pump doesn't turn on when I activate the Aux 1 output.  I can hear the fuel pump relay actuate, though.  The Aux 1 output is hooked up to the low side of the fuel pump relay.  

Documentation says that Fault state on Aux output "indicates the hardware is not happy"...which I'm not quite sure what to make of.   Any clue about what kind of problem I should be looking for? 



PC Datalog - outputs faulting.llgx

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On the other auxes that are off they are constantly watching voltage on their pins, it the voltage drops below 2/3 of battery voltage then they are considered shorted and will report a fault.  So it sounds like there is something wrong with the power supply to those relays - when you activate aux 1 it must be pulling the voltage supply on all the other relays down. 

Check the resistance of the fuel pump relay to start with to confirm it is not shorted internally.  Be aware there are also 2 different pinouts for ISO relays which has caught me out before.  If you had a mix of type A & B it could cause funky stuff.



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