Locks: Description and Operation
POWER LOCKSPower Door Locks
The Viper uses electric door latches to accomplish opening and closing of the vehicle doors and electronics to accomplish the lock function that was typically performed with linkage inside the door.
The system utilizes electric latches and switches both inside and outside the vehicle. These switches are inputs to the Entry Module and if the conditions are correct, the entry module will unlatch the doors. The lock function is simply the ignoring of the switch inputs that would normally open the doors. There is no mechanical lock linkage inside the door. This results in fewer moving parts and problems associated with packaging the linkage mechanisms. The outside door handle and inside door handles control micro switches that are the inputs to the entry module. Located below the inside door switches are the lock switches with LED indicators. The LED lock indicator informs the driver and passenger of the lock status of the doors. If the light is ON, the doors are unlocked. If there is no activity for approximately one minute (input to the entry module) and the key is in the ON or OFF position, the LED will be turned OFF to reduce battery draw.
Fig. 1 Remote Keyless Entry (RKE) Transmitter:
Remote Keyless Entry
The Viper utilizes an Entry Module. The Entry Module provides Remote Keyless Entry (RKE) functions as well as opening or unlatching of the doors. The RKE system allows locking and unlocking as well as arming and disarming of the security system with a hand held radio frequency transmitte. The transmitter sends out a rolling code for high vehicle security. The transmitter has two buttons for operation. They are LOCK and UNLOCK.
The UNLOCK button will unlock both the drivers and passenger side doors. Upon pressing the LOCK button, the horn will sound a short CHIRP to notify that the all door lock signal was received. The driver and passenger lock switches are wired in parallel and form one input to the entry module. When the entry module receives a lock input, both doors are locked. When an unlock signal is input to the entry module, both doors are unlocked and the park/tail lamps are flashed ON and OFF twice. If the key is ON, and an inside door handle input is seen and vehicle speed is below 8 to 13 Km/h (5 to 8 mph), both doors will be unlocked. The lock switch is a momentary contact type switch and either door will lock or unlock the entire vehicle. The key fobs are unique to the Viper and utilize a rolling code system. The rolling code feature changes the key fob message each time it is used. The key fob message and the receiver message increment together. Under certain conditions with a rolling code system, the receiver and transmitter can fall out of synchronization. The system will accept up to four fob codes.
Automatic Door Locks
Once the vehicle is started and driven to a speed of 8 to 13 Km/h (5 to 8 mph) the doors will automatically lock, therefore, the LED will be extinguished at this time. There is no defeat of the Auto-lock feature.
The only difference from other automatic locking systems is that specific throttle angle is not required for the locks to actuate. It is strictly a speed based system. The vehicle will automatically lock if the vehicle speed is greater than 8 to 13 Km/h (5 to 8 mph) or if CCD communication is lost with Ignition key in the run position. The vehicle will automatically unlock if the key is in the ignition with the driver door open or if an inside handle is actuated while the vehicle is not in motion. The vehicle is entered by pushing the outside door handle. This will activate an electrical switch which is received by the entry module. If the vehicle is unlocked, the entry module will power unlatch the respective door. Similarly, exiting the vehicle occurs by pulling the inside door handle. If the conditions are acceptable, the respective door will unlatch.