Figure 15.62. Location of components of the central locking system: 1 – ignition switch; 2 – ECU unit located on the front passenger side; 3 – door lock switch located in the front passenger door; 4 – fuses and relays for window lifters in the fuse and relay box; 5 – door lock switch located in the driver's door; 6 – front door central locking switch and lock; 7 – rear door central locking switch and lock; 8 – central locking of the luggage compartment door
The central locking system uses door lock modulators installed in each door (figure 15.62). The system consists of switches, modulators, a control unit and electrical circuits connecting all components, as well as a remote control transmitter and receiver.
The locks are blocked by reversing solenoids located in the doors. The lock switches have two operating positions: closed and open. When the switch is pressed, a signal is sent from it to the control unit, which opens or closes the door locks.
On some models, the locking system is combined with the anti-theft system.
Check the central locking system as follows:
If the locking mechanism does not work, first check the integrity of the fuse. Some models also use circuit breakers to protect the locking system.
With the engine off, press the key lock switch and listen for the solenoids to operate. When triggered, they produce a characteristic clicking sound.
If the solenoids are not working, remove and test the switch.
Check the condition of the electrical circuit between the switch, control unit and solenoids.
Also check the reliability of the connection to the ground of the switch and the control unit.
If only one solenoid is not working, remove the door trim and check to see if voltage is supplied to the solenoid when the switch is activated. There should be voltage on one of the wires when the lock is locked, and on the other wire when the lock is unlocked.
If voltage is present but the solenoid does not work, replace it.
If there is no voltage to the solenoid, check the relay and the electrical circuit between the solenoid and the control unit.