it's generally good to replace them in pairs, i have a similar issue that popped up after i replaced mine and i had to unplug the door jamb sensor to prevent the alarm from sounding.I'm having issues with my 2009 Eclipse GS passenger door lock actuator. I had issues with my drivers side door not locking/unlocking consistently(sometimes it would unlock/lock) regardless of using the fob or the buttons inside the car. Because of this, I have replaced the motor in the Drivers side actuator and now the drivers side reliably locks/unlocks but now I'm having issues with the passenger side actuator. Passenger side door will lock fine every time but won't unlock with the fob at all(the drivers side lock was visibly moving before changing the motor). I did hear funky things can happen when changing only one motor(this is also very odd), so I replaced the motor in the passenger side actuator and no change. The passenger side door lock actuator worked fine before rebuilding the drivers side actuator.
I have tried researching everywhere about this and I cant find any thing on this issue. I have also tried disconnecting the battery leaving it for 15-20 minutes and reconnecting it with no change. The only problem I have with this is that the alarm goes off when ever I open the drivers side to unlock the passengers door.
i've heard the ETACS goes out when replacing electronics improperly.