Tech A says that when checking tire pressure, the tire should be " cold." Tech B says that the tires should be driven more than 3 miles before checking tire presure. Who is correct?

Technician A is correct.

Explanation:

Technician A is correct because temperature of a tire will affect its pressure reading.

Tires attract heat because of their dark colour and then motion on the road generates heat. A car owner or technician should know that tire pressure is most accurate when the tire is cold (especially when atmospheric temperature is cool too).

If the tires are driven three miles first, their temperature will be high (due to the rubbing of the tires on the surface of the road). This higher temperature will result in higher per square inch (psi) readings.

Temperature has a great influence on the tire pressure.

Even if the tire is driven up to or more than 3 miles, it should still be left to cool, before tire pressure is checked.

The tire manufacturer's rating should be the maximum possible tire pressure. If an abnormal reading is gotten, the gauge should be properly checked.

it was a fall down when it happens

explanation: