Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [automotive]

Questions about the design of electronics for use in an automotive environment. (Questions about the installation and use of automotive electronics are unlikely to be appropriate for this site.)

An application field of electronics that requires high reliability and fail-safe systems. Applications can vary widely in temperature ranges and have a wide voltage range, typically 12 V (or 24 V) while off, and higher when on.

Automotive-grade parts are typically better than consumer and commercial-grade parts, near equal to -grade parts, but not as high quality as military or aerospace-grade parts, though this varies based on manufacturer. Military-grade parts are often mandated by law or government regulation/standards.

Questions about connecting electrical devices to a car, or about car repair, may be better suited to the Motor Vehicle Maintenance & Repair Stack Exchange.

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Why does a Tesla car use an AC motor instead of a DC one?

I was just watching a mega factory video and wondered why they use an AC motor which requires a power inverter instead of DC which may be powered directly from their DC battery? Introducing an inverter means more cost (weight, controller, etc). Are…
wizzup
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Will radar/lidar still work when every car is equipped with them?

Self driving cars rely on cameras, radar, and lidar to recognize the environment around them. Cameras of course don't interfere with each other, since they are passive sensors. Since a signal received directly from another transmitter is much…
crj11
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Why are there so many relays used in a car, instead of transistors?

Recently I did some work on my car electric circuits. I see many relays are used in car circuits. These relays are used for simple switching, and I wonder why these circuits are based on relays and not on transistors or other electronic components…
Al Kepp
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Why do we connect a battery to ground when jumping a car?

This may seem like a very simple question, but I've searched all over the place and haven't found an answer. When jumping a car, we connect the + end of the charged battery to the + end of the dead battery, and the - end of the charged battery to…
Ken Levinski
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Why are car batteries still so heavy?

Back when I was a kid, car batteries used to be huge heavy lumps of plastic filled with lead and acid. They used to weigh almost as much as a mobile phone (slight exaggeration there, sorry). 45 years later, car batteries still look the same and…
user130311
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Why do car blinkers flash at twice the speed when a blinker light has burned out

On my 1999 Ford Escort, the brake lights double as turn signal blinkers. A left brake light burned out recently and my blinkers went much faster than normal when signaling a left turn. This is a convenient (and embarrassing) way to be alerted to a…
David Costanzo
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How can the contact points of jumper cables handle the hundreds of amps required to start a car?

When jumpstarting a car, you connect those big alligator clamps to the terminals of the batteries. The cables themselves can handle the current just fine, but the contact points between the alligator clamps and the battery is extremely small. I'd…
Daffy
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What is the polarity of a car cigarette lighter adapter?

There is a center pin, and two outside tabs. Which are positive and negative?
Mark Harrison
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Why is the chassis used as ground in automotive electrical circuits

Automotive electronics generally use the metal chassis as the negative ground connector for the DC circuits. Obviously this saves something on wiring. Is there an electrical reason for this approach? (I am not asking why negative instead of…
bib
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Is "automotive" grade always better?

I'm working on the parts list for a number of designs for low-voltage (24 VDC) industrial circuits that have no special safety requirements: so long as they don't catch fire no one could be hurt nor property damaged. But they will be used in…
jonathanjo
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Tesla Car "maximum torque at 0 RPM" - is this correct?

Tesla Model S Wiki I've been watching youtube videos on this car, and everyone states that the crazy accelleration is due to maximum torque at 0 rpm. Doing further research, this car uses an AC induction motor, not a DC motor. From my old lecture…
tgun926
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What does an EV "wall socket charging cable" do?

Known as "Mode 2 charging", this method of charging electric vehicles describes the use of a common household wall socket and common mains voltage (230 v) to charge the vehicle. This is usually done at 10 Amps (2,3 kW) while 16 Amp (3,6 kW) charging…
hadrox
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Using LiFePO4 battery as car battery

I've had an idea of using LiFePO4 battery as replacement for car battery, since 4 of those in series make nominal 12.8V which is very close to standard 12V voltage. And depending on the cell we can parallel some to get required starting current.…
ozzo
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Arduino in car: capacitor for extra 3 sec of power

I want to install an Arduino Uno in a car, powered by a consumer 12V->5V car voltage regulator plugged into the lighter socket. The socket is switched, i.e, there's no power when the motor's off. When I turn off the engine I'd like to keep the Uno…
MrSparkly
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Protection against automotive power supply hazards

I'm looking for a way to protect a small circuit which is to be used inside of a car or truck (12V or 24V power system). The circuit consumes about 12-15W. I use an isolated DC/DC converter module which can regulate 9-36V down to 3.3V. I'm looking…
Nico Erfurth
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