How Heat Affects Your Car's Electronics

Modern vehicles contain more electronic components than ever before—from touchscreen infotainment systems to advanced driver assistance computers, from dashboard cameras to electronic control units managing everything from engine performance to climate control. These systems represent thousands of dollars in value and are surprisingly vulnerable to the extreme temperatures found in Australian vehicles during summer.

Understanding how heat affects your car's electronics helps you take appropriate protective measures and recognise early warning signs of heat-related damage.

How Heat Damages Electronics

Electronic components have defined operating temperature ranges. When temperatures exceed these limits, various forms of damage can occur, from temporary malfunction to permanent failure.

Component Degradation

Semiconductors—the fundamental building blocks of all electronic devices—degrade faster at elevated temperatures. Every 10°C increase in operating temperature roughly doubles the rate of degradation. In a vehicle that regularly reaches 60-70°C internally, electronic components age far faster than their designers intended.

Capacitors, which store electrical charge in circuits, are particularly vulnerable. Heat causes the electrolyte inside capacitors to evaporate, reducing their capacity and eventually causing failure. This is a common cause of electronic failures in aged devices and happens much faster in hot environments.

Thermal Expansion

Different materials expand at different rates when heated. This thermal mismatch creates stress on solder joints and connections as components expand and contract with temperature changes. Over many heating and cooling cycles, connections can crack and fail. This is why intermittent electronic problems often appear after a vehicle has been parked in the sun—the thermal cycling has stressed already-weakened connections.

Battery Damage

Lithium-ion batteries—found in phones, tablets, portable GPS units, and increasingly in vehicle electronics—are extremely sensitive to heat. High temperatures accelerate chemical degradation inside the battery, permanently reducing capacity. In extreme cases, overheated lithium batteries can swell, leak, or in rare cases, catch fire.

Vulnerable Electronic Systems

Infotainment Systems

Modern touchscreen displays contain LCD panels that can be damaged by excessive heat. Prolonged exposure can cause screen discolouration, reduced contrast, or permanent dark spots. The plastic bezels and housings can also warp or crack, affecting both appearance and function.

These systems often include built-in thermal protection that shuts down the unit when it overheats. While this prevents immediate damage, repeated thermal shutdowns indicate the system is operating beyond its intended limits.

Dashboard Cameras

Dash cams are particularly vulnerable because they're mounted on windscreens in direct sunlight. The combination of sun exposure and dark housings that absorb heat creates extreme conditions. Quality dash cams designed for Australian conditions include heat-resistant components and capacitors rather than lithium batteries, but even these benefit from shade protection.

Mobile Devices Left in Cars

Phones, tablets, and laptops left in vehicles face extreme heat that can cause immediate damage. Batteries may permanently lose capacity, screens can be damaged, and in extreme cases, devices may become completely non-functional. Most devices will shut down automatically when they overheat, but damage may already have occurred by this point.

Electronic Control Units

Modern vehicles contain dozens of electronic control units (ECUs) managing various systems. While these are designed for automotive use and more heat-resistant than consumer electronics, they still have limits. Repeated extreme heat exposure can cause premature failure of these expensive components, leading to difficult-to-diagnose problems and costly repairs.

Signs of Heat Damage

Recognising early signs of heat damage allows you to address problems before complete failure occurs.

Warning Signs

• Touchscreen responsiveness issues or dead zones
• Display discolouration or dark patches
• Systems that work when cool but fail or behave strangely after the car heats up
• Batteries that drain unusually fast or won't hold charge
• Random reboots or system crashes
• Unusual sounds from speakers or audio distortion
• Warning lights appearing intermittently

What to Do

If you notice these symptoms, avoid further heat exposure while you investigate. Have the vehicle inspected by a qualified technician who can diagnose whether the issues are heat-related. Continuing to expose damaged electronics to extreme temperatures will accelerate their decline.

Protecting Your Electronics

Use Sun Protection

A comprehensive sun protection strategy—including windscreen shades, side window covers, and window tinting—significantly reduces interior temperatures. The difference can be 20-30°C, often enough to keep temperatures within acceptable ranges for most electronics.

Smart Parking

Whenever possible, park in shade or covered parking. Underground car parks and shaded areas make a substantial difference. If you must park in sun, position the vehicle to minimise direct sunlight on the dashboard where most electronics are located.

Remove Portable Electronics

Take phones, tablets, laptops, and portable GPS units with you when leaving the vehicle. If you must leave them, place them in the boot where temperatures are typically lower than in the cabin. Never leave devices in direct sunlight on dashboards or seats.

Dashboard Camera Considerations

For permanently installed dash cams, invest in a quality unit designed for high temperatures. Some owners choose to remove their cameras during extended parking or when the vehicle will be in sun for many hours. If your camera has a parking mode that keeps it powered, ensure adequate ventilation is possible.

Allow Cooling Before Use

After your car has been parked in the sun, open windows and run the air conditioning before relying on electronic systems. Give touchscreens and other components time to cool to normal operating temperatures. This reduces thermal stress and gives systems time to recover from any heat-induced throttling.

Long-Term Considerations

When purchasing vehicle accessories or aftermarket electronics, consider heat resistance as a key selection criterion. Products designed for the Australian market typically account for our extreme conditions, while generic international products may not.

Quality products often cost more but include components rated for higher temperatures and better thermal management. The additional cost is frequently justified by longer lifespan and more reliable operation in Australian conditions.