Precautionary Items When Wiring
Some have mistaken the Viking View (Green/White) wire as a negative ground. If this wire is grounded you will disrupt the proper operation of the ECU.
This wire could have been different in the past, but will still be green/white
If you DO NOT have a Viking View instrument, this wire must be capped off and not used.
If you DO have a Viking View, simply use for the Viking View ground as instructed with instrument. That means, connect to Viking View ground wire. It does not mean to connect the wire to any ground.
It does not mean to connect the wire to any ground, it IS the ground for the Viking View.