2. The locks are controlled by bidirectional solenoid valves located in the doors. The lock sensors have two operating positions: Lock and Unlock (lock and unlock). The switches send pulses to the VSM control unit, from where voltage is then supplied to the lock solenoid valves.
3. If after carrying out the described checks the fault remains undetected, provide the vehicle to a service station for in-depth diagnostics.
4. Always start diagnostics by checking the condition of the circuit's protective elements. On some vehicles, this system has multiple fuses and circuit breakers. Refer to the electrical diagrams provided at the end of this chapter.
5. Make sure there is power to the switches. If there is no power, inspect the wiring between the fuse box and the switches for opens or shorts.
6. If power is present, check the switch for an internal open circuit. If either switch position results in an open internal circuit, replace the switch. To remove the switch, you need to pry it off with a special flat tool and remove the door/window switch panel (see chapter 11).
7. If the switch circuit is shorted, examine the wiring from the switch to the lock solenoid valve.
8. If one of all the switches does not work, remove the trim panel of the corresponding door (see chapter 11) and make sure that there is voltage on the solenoid valve when the switch is in the working position; in the Lock position, the presence of voltage should be noted on one of the wires. In the Unlock position, the current should flow through one wire, and in the Lock position, through the other.
9. If the voltage supply to the non-working solenoid valve is confirmed, replace it.
10. If the solenoid valve does not work and there is no voltage supplied to it, check the relay circuit for an open or short circuit in the wiring connecting the lock solenoid valve and the relay.
Note: As a rule, the wires break between the door and the body (when opening and closing the door, the wires are bent, which ultimately leads to their breakage).
11. In the described vehicles, the automatic lock system is controlled from the VSM control unit. If the cause of the malfunction remains undetected during the described checks, contact a branded station for diagnostics using a special scanner, which can be used to read the malfunction codes contained in the VSM electronic memory.
Keyless entry system
12. One of the elements of the system is a remote control, from which control signals are sent to the receiver. The receiver sends signals to the door lock actuators.
13. If the remote control does not work within 3m, replace its battery. The normal range of the remote control is about 9 m.
14. The components of the remote control housing are separated using a small screwdriver.
15. The remote control is powered by 3-volt lithium cells, CR2032.
16. Connect and fasten the components of the remote control body.
[The text of the article was obtained from the website: ChevyMan]