84 Z28, trying to hook up my commando keyless entry so that the doors will lock when gear selector lever (auto trans.) is pulled out of park. The wiring diagram that I have shows a pos. hot lead coming out when in reverse to turn on back up lights. I also know that it disables/cuts current to the rear hatch slide switch so rear hatch won't open when in gear. Ideally, I need a positive output lead when lever is removed from park. Only way that I can figure right now is to install a relay. 85 ground, 86 wire tap into rear hatch wire that is connected to lever switch, 30 12v switched, and 87a to the positive switched input of the commando module, 87 not used. Right now doors automatically lock as soon as key is turned on. I hate that. Anyone got better/other ideas? With this set up, the relay coil would stay energized even when ign. switch is off and would draw .160 amps. I have been told that would cause the battery to get dead in relatively short period of time especially in cold weather.

This is why I need a positive lead from gear lever only when it is out of park.

thanks.

 

If I'm thinking correctly, you might want to grab a wiring diagram for a 93 Cavalier with the TH-125 3-speed auto (2.2L). That vehicle had the lock out of park deal... Might want to see how they did it. Thing is, I don't know if that particular car had a BCM or not...

Either that or use 2 relays... One ignition controlled (on the coil side, of course) for battery power to the second relay you mentioned above might work.