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Freeze Frame Data

  1. 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 running or stopped, 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. Techstream displays freeze frame data recorded at five different points: 1) 3 times before the DTC is set, 2) once when the DTC is set, and 3) once after the DTC is set. The data can be used to simulate the vehicle's condition around the time of the malfunction. The data may be helpful in determining the cause of a malfunction. It may also be helpful in determining whether a DTC is being caused by a temporary malfunction.

    The ECM records engine conditions in the form of freeze frame data every 0.5 seconds. Using Techstream, five separate sets of freeze frame data, including the data values at the time when the DTC was set, can be checked.

  2. LIST OF FREEZE FRAME DATA 
    Fig 1: Identifying Freeze Frame Data Recorded Point
    G05188611Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    FREEZE FRAME DATA REFERENCE

    LABEL (Techstream Display) Measurement Item/Range Diagnostic Note
    Injector (Port) Injection period of No. 1 cylinder -
    IGN Advance Ignition advance -
    Calculate Load Calculate load Calculated load by ECM (Included in HV Control ECU)
    Vehicle Load Vehicle load -
    MAF Mass air flow volume If value is approximately 0.0 g/s:
    • Mass air flow meter power source circuit open or shorted
    • VG circuit open or short

    If value is 160.0 g/s or more:
    • E2G circuit open
    Engine Speed Engine speed -
    Vehicle Speed Vehicle speed Speed indicated on speedometer
    Coolant Temp Engine coolant temperature If value is -40°C, sensor circuit open
    If value is 140°C, sensor circuit shorted
    Intake Air Intake air temperature If value is -40°C, sensor circuit open
    If value is 140°C, sensor circuit shorted
    Air-Fuel Ratio Air-fuel ratio -
    Ambient Temperature Ambient temperature -
    Purge Density Learn Value Learning value of purge density -
    Evap Purge Flow Purge flow -
    EVAP (Purge) VSV EVAP purge VSV duty ratio -
    Knock Correct Learn Value Correction learning value of knocking -
    Knock Feedback Value Feedback value of knocking -
    Electromagnetic Clutch Electromagnetic clutch -
    Accelerator Idle Position Whether or not accelerator pedal position sensor detecting idle -
    Throttle Fully Close Learn Throttle valve fully closed (learned value) -
    Fail Safe Drive Whether or not fail safe function executed -
    Fail Safe Drive (Main CPU) Whether or not fail safe function executed -
    ST1 Brake pedal signal -
    System Guard System guard -
    Open Side Malfunction Open side malfunction -
    Throttle Idle Position Whether or not throttle position sensor detecting idle -
    Throttle Require Position Throttle requirement position -
    Throttle Sensor Position Throttle sensor positioning Read value with power switch ON (IG) (Do not start engine)
    Throttle Sensor Position #2 Throttle sensor positioning #2 -
    Throttle Position No.1 Throttle position sensor No. 1 output voltage Read value with power switch ON (IG) (Do not start engine)
    Throttle Position No.2 Throttle position sensor No. 2 output voltage Read value with power switch ON (IG) (Do not start engine)
    Throttle Position Command Throttle position command value Read value with power switch ON (IG) (Do not start engine)
    Throttle Sens Open Pos #1 Throttle position sensor position No. 1 -
    Throttle Sens Open Pos #2 Throttle position sensor position No. 2 -
    Throttle Sens Open #1 (AD) Throttle position sensor No. 1 output voltage (AD) Read value with power switch ON (IG) (Do not start engine)
    Throttle Motor Throttle motor -
    Throttle Motor Current Throttle actuator current -
    Throttle Motor DUTY Throttle actuator -
    Throttle Motor Duty (Open) Throttle actuator duty ratio (open) -
    Throttle Motor Duty (Close) Throttle actuator duty ratio (closed) -
    O2S B1 S2 Heated oxygen sensor output 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 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
    Total FT #1 Total fuel trim -
    Short FT #1 Short-term fuel trim Short-term fuel compensation used to maintain air-fuel ratio at stoichiometric air-fuel ratio
    Long FT #1 Long-term fuel trim Overall fuel compensation carried out in long-term to compensate for a 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
    • OL DRIVE: Open loop due to driving conditions (fuel enrichment)
    • OL FAULT: Open loop due to detected system fault
    • CL FAULT: Closed loop but heated oxygen sensor, which used for fuel control, malfunctioning
    Fuel System Status (Bank 2) Fuel system status (Bank 2)
    • OL (Open Loop): Has hot yet satisfied conditions to go closed loop
    • CL (Closed Loop): Using heated oxygen sensor as feedback for fuel control
    • OL DRIVE: Open loop due to driving conditions (fuel enrichment)
    • OL FAULT: Open loop due to detected system fault
    • CL FAULT: Closed loop but heated oxygen sensor, which used for fuel control, malfunctioning
    Catalyst Temp (B1 S1) Catalyst temperature -
    Catalyst Temp (B1 S2) Catalyst temperature -
    Sub O2S Impedance B1 S2 HO2 sensor impedance (Bank 1 Sensor 2) -
    Initial Engine Coolant Temp Initial engine coolant temperature -
    Initial Intake Air Temp Initial intake air temperature -
    Injection Volum (Cylinder 1) Injection volume -
    Closed Throttle Position SW Closed throttle position switch -
    Engine Oil Pressure SW Engine oil pressure switch signal Always ON while engine is running
    ETCS Actuator Power Whether or not electric throttle control system power input -
    +BM Voltage +BM voltage -
    Battery Voltage Battery voltage -
    Actuator Power Supply Actuator power supply -
    Atmosphere Pressure Atmospheric pressure -
    EVAP Purge VSV EVAP purge VSV -
    Fuel Pump/Speed Status Fuel pump/speed status -
    VVT Control Status (Bank 1) VVT control status (bank 1) -
    Vacuum Pump Vacuum pump ON: Operate
    EVAP System Vent Valve EVAP system vent valve ON: Close
    Electric Fan Motor Electric fan motor ON: Operate
    Tank Bypass VSV Tank bypass VSV -
    TC and TE1 TC and TE1 terminals of DLC3 -
    VVT Aim Angle (Bank 1) VVT aim angle (bank 1) -
    VVT Change Angle (Bank 1) VVT change angle (bank 1) -
    VVT OCV Duty (Bank 1) VVT OCV operation duty (bank 1) -
    Idle Fuel Cut Idle fuel cut ON: when throttle valve fully closed and engine speed over 1,500 rpm
    FC TAU FC TAU Fuel cut being performed under very light load to prevent incomplete engine combustion
    Ignition Ignition -
    Cylinder #1 Misfire Count Cylinder #1 misfire rate Displayed only during idling
    Cylinder #2 Misfire Count Cylinder #2 misfire rate Displayed only during idling
    Cylinder #3 Misfire Count Cylinder #3 misfire rate Displayed only during idling
    Cylinder #4 Misfire Count Cylinder #4 misfire rate Displayed only during idling
    All Cylinders Misfire Count All cylinder misfire rate Displayed only during idling
    Misfire RPM Misfire RPM -
    Misfire Load Misfired load -
    Misfire Margin Misfire monitoring -
    Engine Run Time Accumulated engine running time -
    Time after DTC Cleared Cumulative time after DTC cleared -
    Distance from DTC Cleared Accumulated distance from DTC cleared -
    Warmup Cycle Cleard DTC Warm-up cycle after DTC cleared -
    Requested Engine Torque Requested engine torque -
    HV Target Engine Speed HV target engine speed -
    Actual Engine Torque Actual engine torque -
    Estimated Engine Torque Estimated engine torque -
    Engine Run Time Engine run time -
    Request Engine Run Time Request engine run time -
    Judge Time Engine Ignition Judge time engine ignition -
    Judge Time Engine Output Judge time engine output -
    Estimated Intake Port Temp Estimated intake port temperature -
    Fuel Level Fuel level -
    ISC Learning ISC learning -
    F/C for Engine Stop Req Fuel cut for engine stop request -
    Engine Independent Engine independent operation -
    Racing Operation Racing operation -
    Request Warm-up Request warm-up -
    Engine Independent Control Engine independent control -
    Tank Outlet Water Temp Tank outlet water temperature -
    Water Flow Valve Water flow valve -
    ISC Learning Value ISC learning control -
    Direction Value 1 Direction value (water valve) (control side) -
    Direction Value 2 Direction value (water valve) (OBD side) -