I have a DEI 300ESP that has aftermarket door actuators; there's only two of these actuators since it's a regular cab truck. The system was installed by a car alarm shop, not by myself.
It seems to develop a random problem where the driver side door sometimes would not unlock or lock while disarming or arming the alarm. The passenger side lock always work. The thing is, sometimes it works, sometimes it doesn't. It's not completely dead. The motor just won't work.
Originally I thought it was the actuator motor itself, so I replaced them both with new ones. That didn't help.
The door actuator relay setup is exactly like this where the door actuators run parallel. Each wire from the actuator is connected to pin 30 in the relay accordingly.

The relays seem to be fine because if it doesn't work then the passenger door lock wouldn't have worked either.
I thought it was loose connection at the butt connectors to the relay, so I took out butt connectors and soldered the wires directly to the relays. It works, then it doesn't work again.
I disconnect the driver side door actuator wires from the relay and tested the wires with dvm. The connection is good, connect it back up to the relays, still won't unlock/lock while the passenger side actuator works.
Is there anything else I should check?
Does anything happen at all when you try it or is it just "dead"? Does the rod move at all?
I took off the door panel so I can see it. When it works, the rod works, driver side would lock/unlock. EVerything is great like it's supposed to.
But when it doesn't work, the motor won't activate so the rod doesn't move as if there's no current to the actuator itself. I tested the old actuator with a power supply, sure enough it works every time.
Well you have done everything but replace the wires, so that would be the next step.
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Certified Security Specialist
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I just starting to work now

hmm it's just starting to work now. hmm no edit for error.
I didn't want to change the wire, but looks like I may have to. The wire probably wore out because the driver door is opened/closed a lot. I'm gonna get a better wire then.