For my 1989 300 E! Old vacuum system with alarm!


Alarm system is activated and deactivated when using the key in any on the locks. If your car has an alarm system from this time era, the key with a RED Sensor on it will arm and disarm the alarm system. If you lock the car without the key from the passenger door or with a keyless alarm system like the Viper, it will lock the car but without the alarm system! That is why when you unlock the car, the alarm will not go not go off. Unlock the car when it was locked with the key (thus activating the alarm) with the keyless system and guess what, the alarm goes off! Not a big issue for me! I can occasionally lock the car with the key in those situations where an alarm system might be helpful.