Freeze Frame Data

Diagnostic Trouble Code (DTC) Freeze Frame - Range 0-100%: The DTC Freeze Frame Indicates which DTC this freeze frame information is. Clearing the DTCs erases the freeze frame information. Record the information before clearing any DTCs.

Air Fuel Ratio - Range 0:1-25.5:1: The Air Fuel Ratio indicates the air to fuel ratio based on the Oxygen Sensor (02S 1) inputs. The PCM uses the fuel trims to adjust fueling in order to attempt to maintain an air fuel ratio of 14.7:1.

Calc. Air Flow - Range 0-512 g/s: The calculated air flow is a calculation based on the manifold absolute pressure. Several diagnostics use the Air Flow Calculation in order to determine when to run.

Engine Coolant Temperature (ECT) - Range -40°C-215°C (-40°F-419°F): The Engine Coolant Temperature (ECT) sensor sends the engine temperature information to the PCM. The PCM supplies 5 volts to the engine coolant temperature sensor circuit. The sensor is a thermistor. The thermistor changes the internal resistance as the temperature changes. When the sensor is cold indicating the internal resistance is high, the PCM monitors a high voltage. The PCM interprets as a cold engine. As the sensor warms indicating that the internal resistance is decreasing, the voltage signal decreases. The PCM interprets the lower voltage as a warm engine.

Barometric Absolute Pressure (BARO) - Range 11-105 kPa: The Barometric Pressure (BARO) sensor measures the change in the intake manifold pressure. This change results from altitude changes. The value is updated when the ignition is turned ON and at Wide Open Throttle (WOT).

Base Pulse Width Modulation (PWM) Cyl. 1 - Range 0-999.9 mS: The base PWM Cyl. 1 indicates the base Pulse Width Modulation (PWM) or the ON time of the cylinder 1 injector in milliseconds. When the engine load increases, the injector pulse width increases.

Short Term FT - Range (-100% to 100%): The Short Term Fuel Trim represents a short term correction of the fuel delivery. The correction is in response to the amount of time the oxygen sensor voltage is above or below 450 mV. An oxygen sensor voltage below 450 mV indicates a lean air to fuel mixture. If the oxygen sensor has mainly read below 450 mV, the short term fuel trim will increase in order to tell the PCM to add fuel. If the oxygen sensor voltage stays mainly above the threshold, the PCM will reduce the fuel delivery in order to compensate for the indicated rich condition.

Long Term FT - Range (-100% to 100%): The Long Term Fuel Trim (FT) is derived from the short term fuel trim value. The Long Term Fuel Trim (FT) is used for the long term correction of the fuel delivery. A value of the 128 counts (0%) indicates that the fuel delivery requires no compensation in order to maintain a 14.7:1 air to fuel ratio. A value below 128 counts means that the fuel system is too rich and the fuel delivery is being reduced. A value above 128 counts indicates that a lean condition exists for which the PCM is compensating.

Manifold Absolute Pressure (MAP) - Range 11-105 kPa, 0-5.0 Volts: The Manifold Absolute Pressure (MAP) sensor measures the intake manifold pressure. The manifold pressure changes with the engine speed changes and engine load changes. The PCM uses the manifold absolute pressure in order to adjust the fuel delivery and the spark timing.

Engine Speed - Range 0-16384 RPM: The PCM computes the engine speed from the fuel control reference input. The engine speed should remain close to the desired idle under various engine loads with the engine idling.

Loop Status - Range Open/Closed: A Closed Loop displayed indicates that the PCM is controlling the fuel delivery according to the Oxygen Sensor voltage. The PCM controls the air to fuel ratio as close to 14.7:1 as possible.

Vehicle Speed km/h - 0-255 MPH, 0-255 km/h: The PCM converts the vehicle speed sensor into MPH (km/h) for the display. From the PCM, the vehicle speed output is 4000 pulses per mile. The scan tool uses the scan tool uses the class 2 serial data from the PCM in order to obtain the vehicle speed. The instrument panel cluster, the cruise control module, and the multi-function alarm module use the 4000 ppm output.

LOAD - Range 0-100%: The LOAD indicates the engine load based on the manifold absolute pressure. The higher the percentage, the greater the load the engine is under.

Throttle Position (TP) Angle - Range 0-100 %: The PCM computes the Throttle Position (TP) angle from the TP sensor voltage input. The TP angle will auto zero to 0% at idle. The TP voltage will read below 0.90 volt. The TP angle will read 100% at Wide Open Throttle (WOT).