Originally Posted by BBShark
Good stuff. Thanks.
On my C4, I can hear the fuel pump as soon as the key is turned to "ON" before the key is turned to "Start". Is that what is happening with the two "IGN" relays in your diagram?
My ECU ( Megasquirt MS3 Pro) bumps the fuel pump for a couple of seconds as the key is turned to ignition- shuts it off till the engine hits (programmable) 275 RPM- then turns it on. For another safety measure I have a Ford Inertial/rollover switch which will shut the power off to the pump in case something bad happens-
Mounted in the back compartment-
I have a 'blown' fuse (LED type) that lights and tells me the inertia /rollover switch has been tripped.
it's a really neat switch- used for years on Ford Mustangs/Taurus 90-00s And can buy brand new from Summit for about $30.