| 摘要 |
<p>The warning buzzer (1) is linked to the power side of the supply via the light switch (7) and via decoupling diodes (3). If the driver's door is opened, then that courtesy switch (5) links the buzzer to earth, to warn the driver to switch off the lights. The driver's courtesy switch only operates the buzzer, and is separated from the other courtesy switches (11) by other diodes (6). If the ignition is switched on then the earth side of the buzzer is switched to the live side of the supply by a third diode (8) and ignition switch (9). A resistor (4) limits the amount of supply-earth drain in this case. The warning buzzer thus only operates with the headlights on and ignition off, and with the driver's door opened.</p> |
