Freeze Frame Data
- DESCRIPTION
Freeze frame data records the engine conditions (fuel system, calculated load, engine coolant temperature, fuel trim, engine speed, vehicle speed, etc.) when a malfunction is detected. When troubleshooting, it can help determine if the vehicle was running or stopped, the engine was warmed up or not, the air-fuel ratio was Lean or Rich, and other data from the time the malfunction occurred.
HINT:
If it is impossible to duplicate 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 the intelligent tester, 5 separate sets of freeze frame data 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 FREEZE FRAME DATA
Tester Display Measurement Item Diagnostic Note INJECTOR Injection period of No. 1 cylinder - IGN ADVANCE Ignition advance - CALC LOAD Calculated load Calculated load by ECM VEHICLE LOAD Vehicle load - MAF Mass air flow volume If approximately 0.0 g/sec: - Mass air flow meter power source circuit open or short
- VG circuit open or short
If 160.0 g/sec. or more:
- E2G circuit open
ENGINE SPD Engine speed - VEHICLE SPD Vehicle speed Speed indicated on speedometer COOLANT TEMP Engine coolant temperature If -40°C (-40°F), sensor circuit open
If 140°C (284°F) or more, sensor circuit shortedINTAKE AIR Intake air temperature If -40°C (-40°F), sensor circuit open
If 140°C (284°F) or more, sensor circuit shortedAIR-FUEL RATIO Ratio compared to stoichiometric level - PURGE DENSITY Learning value of purge density - EVAP PURGE FLOW Ratio of evaporative purge flow to intake air volume - EVAP PURGE VSV EVAP purge VSV duty ratio - KNOCK CRRT VAL Correction learning value of knocking - KNOCK FB VAL Feedback value of knocking - ACCEL POS #1 Absolute Accelerator Pedal Position (APP) No. 1 - ACCEL POS #2 Absolute APP No. 2 - THROTTLE POS Throttle sensor positioning - THROTTLE POS Throttle position - THROTTLE POS #2 Throttle sensor positioning #2 - THROTTLE MOT Throttle motor - O2S B1 S2 Heated oxygen sensor output Performing INJ VOL or A/F CONTROL function of ACTIVE TEST enables technician to check output voltage of sensor AFS B1 S1 A/F sensor output Performing INJ VOL or A/F CONTROL 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 earned out in long-term to compensate a continual deviation of short-term fuel trim from central valve FUEL SYS #1 Fuel system status - OL (Open Loop): Has not yet satisfied conditions to go closed loop
- CL (Closed Loop): Using A/F 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 A/F sensor, which used for fuel control malfunctioning
O2FT B1 S2 Fuel trim at heated oxygen sensor - AF FT B1 S1 Fuel trim at A/F sensor - AFS B1 S1 A/F sensor current - CAT TEMP B1S1 Estimated catalyst temperature (sensor 1) - CAT TEMP B1S2 Estimated catalyst temperature (sensor 2) - SO2SB1S2 Sub heated oxygen sensor impedance (sensor 2) - INI COOL TEMP Engine coolant temperature at engine start - INI INTAKE TEMP Intake air temperature at engine start - INJ VOL Injection volume - STARTER SIG Starter switch (STSW) signal - PSSW Power steering signal - PS SIGNAL Power steering signal (history) Signal status usually ON until ignition switch turned off CTPSW Closed throttle position switch - A/C SIGNAL A/C signal - PNP SW (NSW) Park/Neutral Position (PNP) switch signal - ELECT LOAD SIG Electrical load signal - STOP LIGHT SW Stop light switch - BATTERY VOLTAGE Battery voltage - ATM PRESSURE Atmosphere pressure - EVAP (Purge) VSV EVAP Purge VSV - FUEL PUMP/SPD Fuel pump/speed status - VVT CTRL B1 VVT control status - VACUUM PUMP Key-off EVAP system leak detection pump status - EVAP VENT VAL Key-off EVAP system vent valve status - FAN MOTOR Electric fan motor - TC/TE1 TC and CG (TE1) terminals of DLC3 - ENG SPEED #1 Engine rpm during No. 1 cylinder fuel cut Output only when FUEL CUT #1 is performed using ACTIVE TEST ENG SPEED #2 Engine rpm during No. 2 cylinder fuel cut Output only when FUEL CUT #2 is performed using ACTIVE TEST ENG SPEED #3 Engine rpm during No. 3 cylinder fuel cut Output only when FUEL CUT #3 is performed using ACTIVE TEST ENG SPEED #4 Engine rpm during No. 4 cylinder fuel cut Output only when FUEL CUT #4 is performed using ACTIVE TEST ENG SPEED ALL Average of engine rpm values during fuel cut of No. 1 to No. 4 cylinders Output only when ACTIVE TEST is performed VVT CHNG ANGL#1 VVT angle - VVT OCV DUTY B1 VVT OCV operation duty - FCIDL Fuel cut idle ON: when throttle valve fully closed and engine speed over 3,500 rpm FCTAU Fuel cut during very light load Fuel cut being performed under very light load to prevent engine combustion from becoming incomplete IGNITION Ignition counter - CYL#1 Cylinder #1 misfire Only displayed during idling CYL#2 Cylinder #2 misfire Only displayed during idling CYL#3 Cylinder #3 misfire Only displayed during idling CYL#4 Cylinder #4 misfire Only displayed during idling CYL ALL All cylinders misfire Only displayed during idling MISFIRE RPM Engine speed when misfire occurred - MISFIRE LOAD Engine load when misfire occurred - MISFIRE MARGIN Margin to detect engine misfire - ENG RUN TIME Accumulated engine running time - TIME DTC CLEAR Cumulative time after DTC cleared - DIST DTC CLEAR Accumulated distance from DTC cleared - WU CYC DTC CLEAR Warm-up cycle after DTC cleared -