Bit of an update...
Old set up
Viper terminal wiring as follows:
SET/UNSET (no wire) but linked to OV,
+ve (red wire to OP3 at control unit),
-ve (black wire to 0V AUX at control unit),
alarm (yellow and blue wires),
A/T (green and white wires).
As you'll remeber from above, initial...