Door trigger vs Alarm/Voice Module

Okay. I'm really going to need some of you Car Security Installer Guru's help on this one. I can't get this to work.

First off, my car has a (-) door trigger input. I took my Matrix 3 off from one of my Civics and put it into the other. A buddy of mine installd it into myi first Civic. I just took it off and put it into my other Civic. They're the same exact same car, but I installed it the same exact way.

Everything worked fine. I had a voice module laying around that I had never used until now. After installing it, everything worked fine. Next day, I'd arm the car and my parger-remote would beep again telling me a door was left open. I'd check doors to make sure they were fully closed and when I'd arm the car, my pager-remote would beep again telling me a door was left open. While both doors were shut and the car armed, I'd open the doors and test if the alarm would go off, and no, the alarm would never go off. But after shutting the door, only my voice module would notify me of anything. So, it's like if somebody were to open the door, I would get no notification from either the brain or the voice module that the door were opened. But after if anybody would have broken in and they were nice enough to close the door, then that's the only time that only the voice module would notify me.

Later, I placed an in-line diode (with the band facing towards door trigger circuit) and that helped stop the 2nd beep after arming of the car. It no longer beeped again telling me the door were opened. But the thing is my domelight supervision no longer worked. It was too cold outside and I was frozen. I didn't have time to check to see if the alarm would sound off if I opened the door while the car was armed (after putting in that diode). But the next day, the diode did no use. The 2nd beep happened again. It's driving me nutts.

The following picture will show the wiring. Keep in mind that I forgot to add the wiring of the relay for domelight supervision. Sorry.

I appreciate any help I could get. TIA

First off, I'd like to thank you 2 guys for the feedback.

I took the voice module off and had 200mA (output) connected to a relay then to the negative door trigger line and the door trigger (input) connected to the door trigger line as well. This was the same exact way I had it on my other Civic, when it always worked perfectly. Now, it still thinks the door is open. It's just boggling me why or how it worked the right way before without the use of a diode and now it doesn't.

Anyway, I just got back from Radio Shack with more 1N4001 (50V - 1A) diodes. It's dark out right now and I have no garage or anything. My door is just parked out in the public parking lot. I'll the 2 diodes, 1 on the door trigger (input) line coming off from the main Alarm unit and 1 on the door trigger (input) line coming off from the Voice Module and let you guys know how everything goes.

I still can't figure out why the main Alarm unit thinks a door is open (when armed). I don't see how it's getting input from anything. Also, while the car is armed and when the door is opened, neither the main Alarm unit nor the Voice Module senses anything. But only the Voice Module senses when the door is shut. It's just weird. I don't just want to solve the problem, but I also want to figure out what exactly caused the problem. =/