PeachParts Mercedes-Benz Forum - View Single Post - I did it! Keyless entry for your 124 made easy (and less than $100)!

crhenkel · #9 12-29-2007, 11:54 PM

Just my two cents...my vac pump is running slower each month, I figure soon it will give out and the door locks will stop unlocking and I will need a pump. This said, when the car is locked and the alarm is on....I can unlock the car at the trunk and open the trunk before the vac pump has operated enough to build pressure to unlock the doors. So, basically, I walk to the car, unlock the car at the trunk and can open the trunk before the vac actuator at the trunk or the doors activates and unlock the car byt he central unlock system. Not a big deal right now, because a few seconds after I open the trunk the vac system kicks in and all the doors and the fuel door and the trunk unlock vac acctuator operate and everything unlocks. Only issue is this...since the central vac system has not operated and the trunk is open, the trunk pin that triggers the alarm closes when the trunk lid opens and the alarm goes off. Like it should..except I used the key as i am supposed to....why does the alarm go off? Only thing I can see is because the disarm arm action is in the door lock. I open the trunk, the doors are all still locked waiting on the vac pump to build pressure casue it is dying and the alarm goes off, then a second or two later the vac pump opens the doors locks and the alarm shuts it self off. The alarm shuts off due to the vac pump opening the door locks. DOnt know what exactly it is doing it with, but the action that shuts off the alarm is my vac pump unlocking the doors, not me unlocking or opening the trunk...SO, by using an unlocking module that triggers the vac pump to unlock the doors, you will by proxie, disarm the alarm in the process...At least that is what is occuring in my 190E .