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OBD System Operation Chart

RELATIONSHIP BETWEEN MIL, DTC, CONSULT AND DETECTABLE ITEMS
- When a malfunction is detected for the first time, the Diagnostic Trouble Codes (DTC) and the freeze frame data are stored in the Engine Control Module (ECM) memory.
- When the same malfunction is detected in two consecutive trips, the Malfunction Indicator Lamp (MIL) will come on. For details, refer to "Two Trip Detection Logic".
- The MIL will go off after the vehicle is driven three times with no malfunction. The drive is counted only when the recorded driving pattern is met (as stored in the ECM). If another malfunction occurs while counting, the counter will reset. The MIL will remain on until the vehicle is driven (in the recorded driving pattern) three times with no malfunction.
- The DTC and the freeze frame data can be displayed until the vehicle is driven 40 times (except for Misfire and Fuel Injection System). For Misfire and Fuel Injection System, the DTC and freeze frame data can be displayed until the vehicle is driven 80 times. The "TIME" IN "SELF-DIAGNOSTIC RESULTS" mode of CONSULT will count in response to the number of times the vehicle is driven.




SUMMARY CHART




DRIVING PATTERNS FOR "MISFIRE" - FUEL INJECTION SYSTEM
*1: When the same malfunction is detected in two consecutive trips, MIL will light up.
*2: MIL will go off after vehicle is driven three times (pattern 0) without any malfunctions.
*3: When a malfunction is detected for the first time, the DTC and the freeze frame data will be stored in ECM.
*4: The DTC and the freeze frame data will not be displayed any longer after vehicle is driven 80 times (pattern B) without the same malfunction.
(The DTC and the freeze frame data still remain in ECM.)
*5: Other screen except DATA MONITOR (AUTO TRIG) can not display the malfunction.
*6: DATA MONITOR (AUTO TRIG) can display the malfunction at the moment it is detected.
*7: The malfunction can not be displayed because the timing to set DATA MONITOR (AUTO TRIO) screen was missed against the NO detection.
*8: The DTC and the freeze frame data will not be displayed any longer after vehicle is driven 80 times (pattern B) without the same malfunction.
(The DTC and the freeze frame data still remain in ECM.)

EXPLANATIONS







Driving pattern B means vehicle operation is as follows:
All components and systems should be monitored at least once by the OBD system.
- The B counter will reset when the malfunction is detected twice regardless of the driving pattern.
- The B counter will count the number of times driving pattern B is satisfied without the malfunction.
- The DTC will not be displayed after the B counter reaches 80.


Driving pattern C means vehicle operation is as follows:
1) Driving pattern A should be satisfied.
2) The following conditions should be satisfied at the same time:
- Engine speed: (Engine speed in the freeze frame data) 1375 rpm
- Calculated load value: (Calculated load value in the freeze frame data) x (1 ± 0.1) [%]
- Engine coolant temperature (T) condition:
- When the freeze frame data shows lower than 70°C (158°F), "T" should be lower than 70°C (158°F)9.
- When the freeze frame data shows higher than or equal to 70°C (158°F), "T" should be higher than or equal to 70°C (158°F).

Example: If the stored freeze frame data is as follows:
- Engine speed: 850 rpm
- Calculated load value: 30%
- Engine coolant temperature: 80°C (176°F)

3) To be satisfied with driving pattern C, the vehicle should run under the following conditions:
- Engine speed: 475 - 1,225 rpm
- Calculated load value: 27 - 33%
- Engine coolant temperature: more than 70°C (158°F)

- The C counter will be cleared when the malfunction is detected regardless of (1), (2). (*1 in "OBD SYSTEM OPERATION CHART")
- The C counter will be counted up when (1), (2) are satisfied without the same malfunction.
- The MIL will go off when the C counter reaches 3. (*2 in "OBD SYSTEM OPERATION CHART")




DRIVING PATTERNS EXCEPT FOR "MISFIRE (EXHAUST QUALITY DETERIORATION)" - FUEL INJECTION SYSTEM
*1: When the same malfunction is detected in two consecutive trips, MIL will light up.
*2: MIL will go off after vehicle is driven three times (pattern B) without any malfunctions.
*3: When a malfunction is detected for the first time, the DTC and the freeze frame data wilt be stored in ECM.
*4: The DTC and the freeze frame data will not be displayed after vehicle is driven 40 times (pattern A) without the same malfunction.
(The DTC and the freeze frame data still remain in ECM.)
*5: Other screen except DATA MONITOR (AUTO TRIG) cannot display the malfunction.
*6: DATA MONITOR (AUTO TRIG) can display the malfunction at the moment it is detected.
*7: The malfunction can not be displayed because the timing to set DATA MONITOR (AUTO TRIG) screen was missed against the NG detection.
*8: The DTC and the freeze frame data will not be displayed after vehicle is driven 40 times (pattern A) without the same malfunction.
(The DTC and the freeze frame data still remain in ECM.)

EXPLANATIONS





- The A counter will be cleared when the malfunction is detected regardless of (1) - (4).
- The A counter will be counted up when (1) - (4) are satisfied without the same malfunction.
- The DTC will not be displayed after the A counter reaches 40.


Driving pattern B means vehicle operation is as follows:
All components and systems should be monitored at least once by the OBD system.
- The B counter will be cleared when the malfunction is detected twice regardless of the driving pattern (*1 in "OBD SYSTEM OPERATION CHART").
- The B counter will be counted up when driving pattern B is satisfied without any malfunctions.
- The MIL will go off when the B counter reaches 3 (*2 in "OBD SYSTEM OPERATION CHART").



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