Scan Tool Freeze Frame: Your Window into Engine Sensor Data

Is it true that a scan tool freeze frame will display engine sensor data at the time the code sets?

a. True
b. False

Final answer: True

A scan tool freeze frame indeed displays engine sensor data at the time a trouble code is set, providing invaluable information for vehicle diagnostics.

Explanation: The statement that a scan tool freeze frame will display engine sensor data at the time the code sets is true. A freeze frame is a snapshot of the operating conditions at the time of an emissions-related fault. This function of the scan tool is particularly useful for diagnostics, as it permits the technician to view the parameters such as engine speed, fuel trims, and air temperature among others, at the exact moment a trouble code was triggered.

For example, if a vehicle sets a fault code for an engine misfire, the freeze frame data may show that the engine was running at 2500 rpm with a coolant temperature of 90 degrees Celsius when the code was set. This vital information can assist in pinpointing intermittent issues which may only occur under certain conditions, aiding in a more efficient diagnostic process.