Anybody who’s ever worked on a sunroof is familiar with how hot the roof of a vehicle can get. A few square feet of sheet metal acts as a nice collector and heat sink in direct sunlight.
It’s tough on thin layer of foam between the headliner fabric and the backing board, and the adhesives that hold the sandwich together. Drooping headliners are not uncommon, even though they’re serve no duty other than as decoration, and receive no direct contact or wear. Refinishing them requires an adhesive that is both strong and heat resistant.
Modern vehicle designs with steeply raked windshields result in more dashboard surface area, and more exposure to sunlight, and a dark-colored dash, as they often are, adds to that. So the glovebox, sitting below that nice heat collector, is my guess as the hottest of the candidates.
Between the center console, and under the driver’s seat, the latter sees the least exposure, and is unenclosed, so it will be the cooler of the two. The floor contains most of the sound insulation material in a car, and between it and the carpeting, is well insulated from ground heat, as well as that generated by components like the catalytic converter and the exhaust system.
I have lights in the door (Pro Seeker2, FW3A 7a), center console (FW3A 1a), ashtray (S1R Baton I, Prometheus Beta), and in the back with my tools (Noctigon Meteor 219c, Olight H1R & H2R, a Black Diamond Storm). South Florida is brutal in the summer so I’m sure I shouldn’t be keeping all this LiIons in my truck but I like to be prepared for anything.
I hear ’ya Watermancris, there’re other lights in the car, but only a thrower and a floody in the glovebox. There’s also a lighter plug-in corded handheld light (no batteries) and both a headlamp and a stand-up work light but they’re in trunk for emergencies, didn’t mention the trunk lights as it wasn’t part of the Poll
The center console was the hottest,
The dash glovebox in the middle,
And under the seat was the coolest.
I was leaning toward the dash being the hottest place till I saw the data.
On this car there is the airbag and AC ductwork between the glovebox and the hot dash or engine compartment. I’ll bet there is 10 to 12 inches of stuff between the box and the top of the dash.
The center compartment only has a thinly padded top. The sides are a single layer of plastic.
140+ degrees is darned warm. That’s warmer than tool makers say to use. A naked powertool sitting in the sun can certainly be hotter than that.
Yet there must be tens of thousands of cordless power tools baking away on jobsites across the country and I don’t really recall any stories of fires. Still, those batteries are not in bomb tubes (err flashlights).
I haven’t replaced my car light, but when I do it will be using Eneloop Pros only and stored in a “”secret compartment”:Where is the secret hidden compartment in a Toyota Prius? - YouTube that should stay pretty cool anyway. My car has plenty of NiMh cells in it, I’m not worried about those
Here is the longer version that makes it a bit easier to guess where the hottest place in the car is located.
Remember this run was taken on a day 17F cooler than the first run.
So using the worst place in the first test as a control, on this run…
In descending order of “hotness”
6 Blue – Roof Console - Hottest
5 Yellow – Front Seat Area (air temp)
4 Green – Trunk
3 Orange – Center Console - Coolest
And from the first run
3 Center Console – Hottest
2 Glove Box – Cooler
1 Under the Drivers Seat – Coolest
I’ll need to try to repeat this test in the winter and see how that compares.
We don’t really have much of a winter here. One of you from the great frozen north should give this a try.
All the Best,
Jeff