Delay Circuits

Delay circuits are added to vehicles to build in specific time delays in turning on or off electrical devices. For example, most modern vehicles have a time delay built into the interior lights on vehicles. After closing the door, the lamp will often stay on for a predetermined time before slowly turning off. The delay circuit can be constructed from electronic components or it can be programmed into an ECU that controls the circuit. Modern vehicles are increasingly using ECUs with programmed timers to perform time-delay functions.