This should be the relay configuration you need.
This is what you see in a typical automotive SPDT relay. The typical (not necessarily guaranteed) pinout is:
85 - ground
86 - sensor input trigger voltage to key the relay (from your ECU/ECM in this case)
87 - switched input (either 12 volts system power, or the trigger voltage from your ECU/ECM in this case)
30 - switched output (to pin 22 on Skyview in this case)
87a - normally open in cars, but this is where you need to connect ground for the Skyview to see when the relay is off
EDIT: Some may notice I've switched the input and output connections. In automotive applications, pin 30 is the input and 87 is the output. But since we need to supply ground in the OFF condition, I made pin 30 the output, and pins 87 and 87a the inputs. Electrically speaking, it makes no difference anyway, as long as the required connection is made.
Automotive relays are designed to trigger with 12 volts, but will typically trigger with much less than that, so your ECU/ECM should have no trouble activating it. If the voltage from your ECU/ECM is 2 to 15 volts, you can tie pins 86 and 87 together. Then it will trigger both the relay and the Skyview widget. This install can be done with a solid state circuit too, but this is simpler, and it allows you to install the relay in a pigtail on the wiring harness behind the panel to make relay replacement a plug and play operation, should it ever be needed.
The general purpose contacts on the Skyview don't act like a typical voltage sensor. They don't really care about voltage at all, because they aren't really looking for voltage to tell them something is turned on. They're really looking for ground to tell them something is turned off. By the way, Dynon also recommends a 10k ohm resistor inline to to any general purpose contact that ever gets 12 volts, or thereabouts, sent to it.
I did something similar to this some time ago, for an entirely different purpose. The parts I used SHOULD be the same for you, so you can try them if you want. These are ten packs though, and you only need one, so find a smaller quantity if you can to save money. You also don't need 30 amp if you can find smaller, but that's a typical rating in automotive relays.
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Here's a reference on relays:
www.the12volt.com
Sorry I didn't see this sooner (I should have). I started reacting to what I was reading first, without thoroughly reading all the rest, both here and in the manual.