Basic structure and working principle
Components
Power cable: usually red (positive, connected to the battery or ignition switch power) and black (negative, iron).
Fuse: connected in series in the positive line to prevent overload or short circuit.
Plugs and Sockets: The cigarette lighter socket provides 12V DC and the plug triggers the internal spring contacts to supply power when plugged in.
Control Module: Some models manage power on/off through a relay or Body Control Module (BCM).
How it works
When the cigarette lighter is plugged in, the internal spring contact closes and current passes through the heating wire to heat it up.
When the cigarette lighter is pulled out, the contacts are disconnected and the circuit is automatically closed.
Common Troubleshooting
Cigarette lighter does not respond
Check the fuse: located in the engine compartment or the inner fuse box of the instrument panel (refer to the vehicle manual to find the corresponding location).
Check the wiring: Use a multimeter to measure the voltage of the socket, if there is no voltage, you need to check whether the wiring is disconnected.
Clean contacts: oxidation or dirt may cause poor contact.
Socket overheating/burning out
Overloading: Prolonged use of high power devices (e.g. car refrigerator) may exceed the designed load.
Internal short circuit: Check the heating wire for damage and replace the whole socket if necessary.