duh, i had to reveiw my notes....
12 volts if in neutral, 0 volts if in gear... use a 12volt 30/40 amp relay to invert the 12 volts to ground for the black/white neutral safety wire.
other owners have tapped their hood pin to this wire and whenever the vehicle is in neutral and the alarm is armed, their alarm would get triggered. it would appear that this wire shows ground when the vehicle is in neutral.
your best bet is to test with a digital multimeter. attach your red probe to a 12 volt source and use the black probe on the neutral wire. if the meter shows 12 volts while the vehicle is in neutral, then it's a negative wire, if it shows 0 volts then it's a postive wire.
if the neutral safety wire off the ecu is negative, then you can just connect it directly to the black/white wire off the viper 550esp. if it's postive, you will need to invert it to ground, a relay or a low current voltage inverter will do.
just don't use a 12 volt light tester, you may fry either the ecu and/or the neutral switch on the transmission.
i believe the viper needs to check the neutral safety before the status output.
btw, you didn't mention if you have the Subaru Upgrade Security system or not... if so, you will need to remove all the parts of the system etc...
Originally posted by quynce
Thanks for the reply. I was hoping you would jump in on this. I am putting in a DEI unit.
The problem with wiring the neutral safety wire from the ECU directly to the black/white wire is that the ECU throws 12V in neutral, and 0 (ground?) in gear, so it would have the opposite effect, hence the two relays.
Regarding the status output (blue) wire, do you know if it transmits before or after checking the neutral safety wire? Thanks again.