Vehicle equipment — Ohio Permit Test
Vehicle equipment on the Ohio permit test — 7 rules, each with the reason behind it and a question on it while it is fresh.
The rules
Ohio law forbids driving a vehicle on any highway in a condition unsafe enough to endanger a person, and the driver is responsible for that condition before setting off.
You cannot control the other traffic, but the state holds you to the one thing you can control.
No person shall drive or move, or cause or knowingly permit to be driven or moved, on any highway any vehicle or combination of vehicles which is in such unsafe condition as to endanger any person.
A tire is only in safe condition with at least one sixteenth of an inch of tread depth on the road surface and no major bumps, bulges, breaks or tread damage.
Tread is what moves water out from under the tire; worn smooth, it floats instead of gripping.
Tires with a minimum of 1/16-inch tread depth and no major bumps, bulges, or damage
The average motor vehicle must carry two working headlights, one taillight showing red and visible from five hundred feet, two red brake lights visible from five hundred feet, and a white light on the rear license plate.
Every one of those distances is somebody else's warning time, measured from where they can still stop.
Two red stop lights (brake lights) visible from 500 feet when the brakes are applied
A vehicle's turn signals must work and be visible from three hundred feet, with two at the front and two at the rear.
A signal nobody can see at three hundred feet arrives after the decision it was meant to inform.
Turn signals in working order, visible from 300 feet
A vehicle's horn must work, be audible from two hundred feet, and sound like a motor vehicle horn rather than anything else.
The horn is a warning device, so the law cares that it is heard and recognized, not that it is loud.
Horn in good working order, audible from 200 feet, and identifiable as a motor vehicle horn
A windshield must let through seventy percent of light, and the side windows beside the front seat must let through fifty percent, allowing three percent either way.
Tint that stops light stops it in both directions, and at night the loss is yours.
Side windows of front seat: 50% light transmission, plus or minus 3%
A vehicle needs two braking systems: a service brake able to slow, stop and control it, and a parking brake able to hold it still on a grade.
The parking brake is a second system for a reason, and brake failure is the reason.
Service brake that is adequate to slow, stop, and control the vehicle
On the test
Who is responsible for a vehicle being roadworthy before it is driven?
The driver, who must not take an unsafe vehicle onto a highway. You cannot control the other traffic, but the state holds you to the one thing you can control. Digest of Ohio Motor Vehicle Laws, p.7: “No person shall drive or move, or cause or knowingly permit to be driven or moved, on any highway any vehicle or combination of vehicles which is in such unsafe condition as to endanger any person.”
How this works
Most practice tests hand you a bank of questions and leave the manual somewhere else. This one puts them together.
You read one law and the reason behind it, then answer a question on that law while it is still fresh. Get it right and you move on; get it wrong and you have found the gap while it is cheap to fix, not on the morning of the exam.
Learning one rule at a time, and proving it immediately, is what turns a manual you skimmed into something you actually know — and it makes studying feel like getting somewhere rather than like waiting to find out.
What it costs
- One payment, once — not a subscription. Nothing renews and there is nothing to cancel, for an exam you sit one time.
- Free to start: a 10-question test and the first section of cards. No sign-up and no account.
- Paying opens the rest of the cards, unlimited full-length practice tests, and retests built from exactly the questions you got wrong.
- Every level up to Prepared — 3 tests passed in a row.
- Do the work, fail the real exam, and we refund you.
Where these come from
Every rule here is checked against Digest of Ohio Motor Vehicle Laws, published by the Ohio Department of Public Safety, and against the state code itself. Last checked 2026-09-14.