Freeze Frame Data
- DESCRIPTION
The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can be helpful in determining whether the vehicle was moving or stationary, whether the engine was warmed up or not, whether the air-fuel ratio was lean or rich, as well as other data recorded at the time of a malfunction.
HINT:
If it is impossible to replicate the problem even though a DTC is detected, confirm the freeze frame data.
The ECM records engine conditions in the form of freeze frame data every 0.5 seconds. Using a Techstream, five separate sets of freeze frame data, including the data values at the time when the DTC was set, can be checked.
- 3 data sets before the DTC was set.
- 1 data set when the DTC was set.
- 1 data set after the DTC was set.
These data sets can be used to simulate the condition of the vehicle around the time of the occurrence of the malfunction. The data may assist in identifying the cause of the malfunction, and in judging whether it was temporary or not.
- LIST OF FREEZE FRAME DATA LIST OF FREEZE FRAME DATA
Tester Display Measurement Item Diagnostic Note Injector (Port) Injection period of No. 1 cylinder - IGN Advance Ignition timing advance for No. 1 cylinder - Calculate Load Calculated load by ECM - Vehicle Load Vehicle load Load percentage in terms of maximum intake air flow amount MAF Air flow rate from Mass Air Flow (MAF) meter If value approximately 0.0 g/sec: - MAF meter power source circuit open
- VG circuit open or short
If value 271.0 g/sec or more:- E2G circuit open
Engine Speed Engine speed - Vehicle Speed Vehicle speed Speed indicated on speedometer Coolant Temp Engine coolant temperature - If value -40°C (-40°F): sensor circuit open
- If value 140°C (284°F): sensor circuit shorted
Intake Air Intake air temperature - If value -40°C (-40°F): sensor circuit open
- If value 140°C (284°F): sensor circuit shorted
Air-Fuel Ratio Ratio compared to stoichiometric level - Purge Density Learn Value Learning value of purge density Service data Evap Purge Flow Ratio of evaporative purge flow to intake air volume Service data EVAP (Purge) VSV EVAP (Purge) VSV control duty Order signal from ECM Knock Correct Learn Value Correction learning value of knocking Service data Knock Feedback Value Feedback value of knocking Service data Accelerator Position No.1 Accelerator pedal position No. 1 - Accelerator Position No.2 Accelerator pedal position No. 2 - Throttle Position Absolute throttle position sensor Calculated value based on VTA1
Read value with ignition switch ONThrottle Sensor Position Throttle sensor positioning Recognition value for throttle opening angle on ECM
Read value with ignition switch ONThrottle Sensor Position #2 Absolute throttle sensor positioning #2 Recognition value for throttle opening angle on ECM
Read value with ignition switch ONThrottle Motor Throttle actuator - O2S B1 S2 Heated oxygen sensor output voltage for bank 1 sensor 2 Performing Control the Injection Volume or Control the Injection Volume for A/F Sensor function of Active Test enables technician to check output voltage of sensor AFS B1 S1 A/F sensor output voltage for bank 1 sensor 1 Performing Control the Injection Volume or Control the Injection Volume for A/F Sensor function of Active Test enables technician to check output voltage of sensor Short FT #1 Short-term fuel trim of bank 1 Short-term fuel compensation used to maintain air-fuel ratio at stoichiometric air-fuel ratio Long FT #1 Long-term fuel trim of bank 1 Overall fuel compensation carried out in long-term to compensate continual deviation of short-term fuel trim from central value Fuel System Status (Bank 1) Fuel system status (bank 1) - OL (Open Loop): Has not yet satisfied conditions to go closed loop
- CL (Closed Loop): Using heated oxygen sensor as feedback for fuel control
- OLDRIVE: Open loop due to driving conditions (fuel enrichment)
- OLFAULT: Open loop due to detected system fault
- CLFAULT: Closed loop but heated oxygen sensor, which is used for fuel control, malfunctioning
Fuel System Status (Bank 2) Fuel system status (bank 2) AF FT B1 S1 Short-term fuel trim associated with bank 1 sensor 1 - AFS B1 S1 Air fuel ratio sensor output current for bank 1 sensor 1 Value becomes higher when fuel-cut executed under high engine speed Catalyst Temp (B1 S1) Catalyst temperature (associated sensor 1) - Catalyst Temp (B1 S2) Catalyst temperature (associated sensor 2) - Sub O2S Impedance B1S2 Sub heated oxygen sensor impedance (bank 1 sensor 2) - Initial Engine Coolant Temp Initial engine coolant temperature Service data Initial Intake Air Temp Initial intake air temperature Service data Injection Volum (Cylinder 1) Injection volume (Cylinder 1) Quantity of fuel injection volume for 10 times Starter Signal Starter signal (STA terminal input status) - Power Steering Switch Power steering switch - Closed Throttle Position SW Closed throttle position switch - Stop Light Switch Stop light switch status - Battery Voltage Battery voltage - Atmosphere Pressure Atmospheric pressure - EVAP Purge VSV VSV status for EVAP control Active Test support data Fuel Pump/Speed Status Fuel pump/status Active Test support data VVT Control Status (Bank 1) VVT control (bank 1) status Active Test support data Vacuum Pump Key-off EVAP system leak detection pump status Active Test support data EVAP System Vent Valve key-off EVAP system vent valve status Active Test support data Electric Fan Motor Electric cooling fan motor Active Test support data TC and TE1 TC and CG (TE1) terminals of DLC3 Active Test support data Engine Speed of Cyl #1 Engine RPM for cylinder 1 Output only when Check the Cylinder Compression performed using Active Test 51199 rpm: Not performed Active Test Engine Speed of Cyl #2 Engine RPM for cylinder 2 Output only when Check the Cylinder Compression performed using Active Test 51199 rpm: Not performed Active Test Engine Speed of Cyl #3 Engine RPM for cylinder 3 Output only when Check the Cylinder Compression performed using Active Test 51199 rpm: Not performed Active Test Engine Speed of Cyl #4 Engine RPM for cylinder 4 Output only when Check the Cylinder Compression performed using Active Test 51199 rpm: Not performed Active Test Av Engine Speed of All Cyl Engine RPM for all cylinders Output only when Check the Cylinder Compression performed using Active Test 51199 rpm: Not performed Active Test VVT Aim Angle (Bank 1) VVT aim angle (bank 1) VVT duty signal value during intrusive operation VVT Change Angle (Bank 1) VVT change angle (bank 1) Displacement angle during intrusive operation VVT OCV Duty (Bank 1) VVT OCV operation duty Requested duty value for intrusive operation Idle Fuel Cut Fuel cut idle Idle Fuel Cut = "ON" when throttle valve fully closed and engine speed over 2800 rpm FC TAU Fuel cut TAU (Fuel cut during very light load) Fuel cut being performed under very light load to prevent engine combustion from becoming incomplete Ignition Ignition counter to calculated misfire rate - Cylinder #1 Misfire Count Misfire ratio of cylinder 1 This item displayed only when idling Cylinder #2 Misfire Count Misfire ratio of cylinder 2 This item displayed only when idling Cylinder #3 Misfire Count Misfire ratio of cylinder 3 This item displayed only when idling Cylinder #4 Misfire Count Misfire ratio of cylinder 4 This item displayed only when idling All Cylinders Misfire Count All cylinders misfire rate - Multiple Cylinders Misfire Count Multiple cylinders misfire rate - Misfire RPM Average engine speed when misfire occurs - Misfire Load Average engine load when misfire occurred - Misfire Margin Margin to detect engine misfire Misfire detection margin Catalyst OT MF F/C Catalyst overheat misfire prevention fuel cut function availability Service data Cat OT MF F/C History Catalyst overheat misfire prevention fuel cut function history Service data Cat OT MF F/C Cylinder#1 Display of fuel cut operation in No. 1 cylinder (if certain level of misfire malfunction is detected) - Cat OT MF F/C Cylinder#2 Display of fuel cut operation in No. 2 cylinder (if certain level of misfire malfunction is detected) - Cat OT MF F/C Cylinder#3 Display of fuel cut operation in No. 3 cylinder (if certain level of misfire malfunction is detected) - Cat OT MF F/C Cylinder#4 Display of fuel cut operation in No. 4 cylinder (if certain level of misfire malfunction is detected) - Engine Run Time Engine run time - Time after DTC Cleared Time since DTCs cleared - Distance from DTC Cleared Distance traveled since DTCs cleared - Warmup Cycle Cleard DTC Warm-up cycles since DTCs cleared Number of warm-up cycles since DTCs cleared