Limp home mode on GM systems

[Mike Comai]

I'm putting a GM '747 system into a 1979 CJ5.  I was curious if anyone new
what sensors/systems the ECM uses when it enters limp home mode.  I
noticed that on the schematics it looks like the fuel pump is running all
the time when the oil pressure switch is closed(i.e. bypasses the relay) 
and the only reason I can think for that would be if the ECM fails or
enters L.H.M., or the relay fails.  I just wanted to make sure that I
think of all the angles when I do the install, and I'd appreciate any
more info on L.H.M. or any other odities that aren't easy to see.  Thanks,


Mike Comai