Diagnostic Method
- MODE Y (Tank pressure stabilization)
Perform the diagnosis under the conditions, and return the tank pressure to atmosphere.
Tank pressure > 0.9 kPa (67.5 mmHg, 2.7 inHg) after 0.1 seconds:
Cancel the leak check. (Change to Mode A, Tank pressure ≤ 0.9 kPa (67.5 mmHg, 2.7 inHg).)
- MODE Z (Purge control solenoid valve open trouble diagnosis)
DTC P0457
DTC P1443
- Purpose of Mode Z
When performing the leakage diagnosis of EVAP system, CPC have to operate normally. Therefore, mode Z is used to diagnose the CPC open fixation.
If the CPC open fixation trouble is detected, the EVAP system leakage diagnosis is cancelled.
If the CCV closed fixation trouble occurred, negative pressure is generated from the engine to pressure control solenoid valve when pressure control solenoid valve is closed and CPC is opened. Under this condition, the valve cannot be opened for the pressure control solenoid valve structure if the negative pressure is larger than electromagnetic force when pressure control solenoid valve solenoid is set to ON in order to open the valve.
- Diagnostic method
CPC open fixation diagnosis is performed in mode Z as shown in the figure below.
- Diagnosing function of CPC [P0457]
CPC functional diagnosis is performed by monitoring the tank pressure in Mode Z.
Normality Judgment
Make OK judgment in 3 seconds after Mode Z started, and change to Mode A if OK.
- Judgment Value JUDGMENT VALUE (NORMALITY JUDGMENT)
Malfunction Criteria Threshold Value DTC (Tank pressure when Mode Z started) -(Tank pressure when Mode Z finished) ≤ 0.4 kPa (3 mmHg, 0.12 inHg) P0457 - Normal Operation
- evptez - evptezha ≤ 0.4 kPa (3.0 mmHg, 0.12 inHg)
Judge normal when calculation is completed.
Abnormality Judgment
If OK judgment cannot be made, extend Mode Z 16 seconds more, and judge NG when all the criteria below are completed in 16 seconds.
- Judgment Value JUDGMENT VALUE (ABNORMALITY JUDGMENT)
Malfunction Criteria Threshold Value DTC (Tank pressure when Mode Z started) - (Tank pressure when Mode Z finished) > 0.6 kPa (4.5 mmHg, 0.18 inHg) P0457 Tank pressure when Mode Z started ≤ 1.43 kPa (10.7 mmHg, 0.42 inHg) Time for no fuel rolling of 2 l or more ≥ 40 seconds
Time Needed for Diagnosis : 16 seconds
Malfunction Indicator Light Illumination : Illuminates when malfunction occurs in 2 continuous driving cycles.
Finish the Evap. diagnosis when making NG judgment for purge control solenoid valve open fixation. Cancel the Evap. diagnosis when the OK/NG judgment for drain valve close fixation and purge control solenoid valve open fixation cannot be made in Mode Z.
- Purge Control Solenoid Valve Open Fixation
- evptezini ≤ 1.43 kPa (10.7 mmHg, 0.42 inHg)
- No fuel rolling of above 2 l (0.79 US gal, 0.67 Imp gal) for more than 40 seconds.
Judge normal when these calculations are completed.
Cancel the evaporative emission control system diagnosis when the OK/NG judgment for purge control solenoid valve open fixation cannot be made in Mode Z.
- Leak Diagnosis
DTC P0442
DTC P0456
DTC P0457
- Diagnostic method
- The diagnostic method consists of creating a sealed vacuum in the fuel tank and then determining the presence of leakage from the speed at which the tank internal pressure returns to atmospheric pressure.
- The diagnosis is divided into the following five phases.
Mode A:
Calculate the tank pressure variation amount (P1) in Mode A. After calculating P1, change to Mode B.
Mode B:
Introduce the negative pressure in the intake manifold to the tank.
Approx. 0 → -1.4 kPa (0 → -10.5 mmHg, 0 → -0.41 inHg) (0.04-in diagnosis)
Approx. 0 → -3.05 kPa (0 → -22.9 mmHg, 0 → -0.9 inHg) (0.02-in diagnosis)
When the pressure above (desired negative pressure) is reached, Mode C is entered.
In this case, if the tank pressure does not become the desired negative pressure, judge that there is a large leakage in the system.
Judge NG when the malfunction criteria below is completed.
Finish the Evap. diagnosis when judging large leak (35 seconds) in 0.04-inch diagnosis. Cancel the diagnosis (62 seconds) in 0.02-inch diagnosis.
Abnormality Judgment
Judge NG (large leak) when the criteria below are completed in the specified time.
Specified Time
High vehicle speed mode (Vehicle speed > 72 km/h (45 MPH)); 35 seconds
Low vehicle speed mode (Vehicle speed < 72 km/h (45 MPH)); 18 seconds
- Judgment Value JUDGMENT VALUE (ABNORMALITY JUDGMENT)
Malfunction Criteria Threshold Value DTC (0.04-inch diagnosis) P0457 (Tank pressure when Mode Z started) -(Min. value of tank pressure during Mode B) < 0.3 kPa (2.25 mmHg, 0.089 inHg)
Cancel the diagnosis when the NG judgment does not completed in the specified time.
Mode C:
Stop the introduction of negative pressure. (Wait until the tank pressure returns to the start level of P2 calculation.)
Change to Mode D when the tank pressure returns to the start level of P2 calculation.
Judge immediate OK and change to Mode E when it does not return in spite of spending the specified time.
| Tank pressure when P2 calculation started | Time for immediate OK judgment | |
|---|---|---|
| 0.04-inch diagnosis | -1.3 kPa(-9.75 mmHg, -0.38 inHg) | 16 seconds |
| 0.02-inch diagnosis | -3 kPa (-22.5 mmHg, - 0.89 inHg) | 20 seconds |
Mode D:
Monitor the pressure variation in the tank in Mode D. In this case, the tank pressure increases, that is, the pressure becomes as high as the atmospheric air pressure, because evaporator is generated. However, if any leakage exists, the pressure increases additionally in proportion to this leakage. The pressure variation of this tank is P2.
After calculating P2, perform small leak diagnosis and change to Mode E if normal. Complete Evap. diagnosis if abnormal.
- After Diagnosis
Assigning P1 and P2, which are tank variations measured in Mode A and Mode B, to the formula below, judge the small leakage of the system. If the measured judgment value exceeds the threshold value, it is judged to be malfunction.
- 0.04-inch Diagnosis
Abnormality Judgment
Judge NG when the criteria below are completed and judge OK when not completed.
- Judgment Value JUDGMENT VALUE (ABNORMALITY JUDGMENT) 0.04-INCH DIAGNOSIS
Malfunction Criteria Threshold Value DTC P2- (1) x P1
P2 = Tank pressure varying at a specified time in mode D.
P1 = Tank pressure varying at a specified time in mode A.Map 1 P0442 (1) P1 ≥ 0: 1.5 P1 < 0: 1 - Map 1 FUEL TEMPERATURE REFERENCE MAP 1
Fuel temperature 25°C (77°F) Fuel temperature 30°C (86°F) Fuel temperature 35°C (95°F) Fuel temperature 40°C (104°F) Fuel temperature 45°C (113°F) Fuel remaining 10 l (2.6 US gal, 2.2 Imp gal) 0.34 kPa (2.53 mmHg, 0.10 inHg) 0.36 kPa (2.72 mmHg, 0.11 inHg) 0.44 kPa (3.28 mmHg, 0.13 inHg) 0.45 kPa (3.38 mmHg, 0.13 inHg) 0.46 kPa (3.47 mmHg, 0.14 inHg) Fuel remaining 20 l (5.3 US gal, 4.4 Imp gal) 0.44 kPa (3.28 mmHg, 0.13 inHg) 0.49 kPa (3.65 mmHg, 0.14 inHg) 0.53 kPa (3.94 mmHg, 0.14 inHg) 0.53 kPa (3.94 mmHg, 0.14 inHg) 0.53 kPa (3.94 mmHg, 0.14 inHg) Fuel remaining 50 l (13.2 US gal, 11.0 Imp gal) 0.53 kPa (3.94 mmHg, 0.14 inHg) 0.54 kPa (4.03 mmHg, 0.16 inHg) 0.56 kPa (4.22 mmHg, 0.17 inHg) 0.64 kPa (4.78 mmHg, 0.19 inHg) 0.66 kPa (4.97 mmHg, 0.2 inHg) - 0.02-inch Diagnosis
Abnormality Judgment
Judge NG when the criteria below are completed.
- Judgment Value JUDGMENT VALUE (ABNORMALITY JUDGMENT)
Malfunction Criteria Threshold Value DTC P2 - (1) x P1
P2 = Tank pressure varying at a specified time in mode D.
P1 = Tank pressure varying at a specified time in mode A.> Map 2 P0456 (1) P1 ≥ 0: 1.5 P1 < 0: 1 - Map 2 FUEL TEMPERATURE REFERENCE MAP 2
Fuel temperature 20°C (68°F) Fuel temperature 25°C (77°F) Fuel temperature 30°C (86°F) Fuel temperature 35°C (95°F) Fuel temperature 40°C (104°F) Fuel remaining 10 l (2.6 US gal, 2.2 Imp gal) 0.46 kPa (3.47 mmHg, 0.14 inHg) 0.46 kPa (3.47 mmHg, 0.14 inHg) 0.46 kPa (3.47 mmHg, 0.14 inHg) 0.46 kPa (3.47 mmHg, 0.14 inHg) 0.80 kPa (6.00 mmHg, 0.24 inHg) Fuel remaining 20 l (5.3 US gal, 4.4 Imp gal) 0.53 kPa (3.94 mmHg, 0.15 inHg) 0.53 kPa (3.94 mmHg, 0.15 inHg) 0.59 kPa (4.41 mmHg, 0.17 inHg) 0.66 kPa (4.97 mmHg, 0.2 inHg) 1.14 kPa (8.53 mmHg, 0.34 inHg) Fuel remaining 30 l (7.9 US gal, 6.6 Imp gal) 0.54 kPa (4.03 mmHg, 0.16 inHg) 0.59 kPa (4.41 mmHg, 0.17 inHg) 0.65 kPa (4.88 mmHg, 0.19 inHg) 0.65 kPa (4.88 mmHg, 0.19 inHg) 1.11 kPa(8.34 mmHg, 0.33 inHg)
Normality Judgment
Judge OK when the criteria below are completed.
- Judgment Value JUDGMENT VALUE (NORMALITY JUDGMENT)
Malfunction Criteria Threshold Value DTC P2 - (1) x P1 < Map 3 P0456 (1) P1 >0: 1.5 P1 < 0: 1 - Map 3 FUEL TEMPERATURE REFERENCE MAP 3
Fuel temperature 20°C (68°F) Fuel temperature 25°C (77°F) Fuel temperature 30°C (86°F) Fuel temperature 35°C (95°F) Fuel temperature 40°C (104°F) Fuel remaining 10 l (2.6 US gal, 2.2 Imp gal) 0.33 kPa (2.48 mmHg, 0.097 inHg) 0.33 kPa (2.48 mmHg, 0.097 inHg) 0.39 kPa (2.91 mmHg, 0.115 inHg) 0.39 kPa (2.91 mmHg, 0.115 inHg) 0.39 kPa (2.91 mmHg, 0.115 inHg) Fuel remaining 20 l (5.3 US gal, 4.4 Imp gal) 0.39 kPa (2.91 mmHg, 0.115 inHg) 0.43 kPa (3.23 mmHg, 0.127 inHg) 0.5 kPa (3.75 mmHg, 0.148 inHg) 0.65 kPa (4.88 mmHg, 0.192 inHg) 0.86 kPa (6.45 mmHg, 0.254 inHg) Fuel remaining 30 l (7.9 US gal, 6.6 Imp gal) 0.31 kPa (2.34 mmHg, 0.092 inHg) 0.36 kPa (272 mmHg, 0.107 inHg) 0.39 kPa (2.91 mmHg, 0.115 inHg) 0.39 kPa (2.91 mmHg, 0.115 inHg) 0.39 kPa (2.91 mmHg, 0.115 inHg) If not judged OK or NG, repeat the diagnosis.
Malfunction Indicator Light Illumination : Illuminates when malfunction occurs in 2 continuous driving cycles.