Chrysler Voyager Forum : “Valet code - central locking doesn't works”

Valet code - central locking doesn't works

Sometimes our Voyager (2.4 SE deluxe 2001) goes automatically into the valet code. The central locking doesn't works and we can't start the car. After manually opening the door we often hear a clicking sound. It finally succeeds to the valet with the numeric code (on steering column) and then we can start the car. Who knows how it is that the car automatically into the valet code goes and making the ticking sound and how to solve?  Our car is fitted with a Clifford Concept 300 system.  Hope someone can tell us more about this problem...
(I hope you'll understand my English)