If you park your vehicle under direct sunlight and leave your lights or air conditioning (AC) on, several things can happen:
Battery Drain: Leaving your lights or AC on while the engine is off can quickly drain your vehicle's battery. The battery powers the electrical systems, including the lights and AC, and if it's not being recharged by the engine, it will eventually become depleted.
Overheating: Direct sunlight can significantly increase the temperature inside your parked vehicle. Running the air conditioning while parked may initially provide relief from the heat, but if the engine is not running, the AC system will eventually lose its cooling capacity as the battery drains. The vehicle's interior may become uncomfortably hot, and the AC system may fail to cool the air adequately.
Risk of Engine Overheating: If the engine is off, it's not actively circulating coolant and maintaining the engine temperature. If the ambient temperature is high and the sunlight is directly hitting the vehicle, the engine may be at risk of overheating. This situation can lead to potential engine damage and may require costly repairs.
Fuel Consumption: Keeping the lights on while the engine is off won't have a significant impact on fuel consumption since the lights draw power from the battery. However, running the air conditioning without the engine running puts additional strain on the battery, which, in turn, may require the engine to be started more frequently. This can result in increased fuel consumption over time.
To avoid these issues, it is generally recommended to turn off all electrical systems, including lights and the AC, when you park your vehicle and switch off the engine. If you're concerned about the interior temperature, consider using sunshades or parking in shaded areas to minimize direct sunlight exposure.