Engine Controls - (2UZ-FE) - Diagnostics: Other Toyota Tundra I рестайлинг

READINESS MONITOR DRIVE PATTERN

PURPOSE OF THE READINESS TESTS

1. The On-Board Diagnostic (OBD II) system is designed to monitor the performance of emission-related components and report any detected abnormalities in the form of Diagnostic Trouble Codes (DTCs). Since the various components need to be monitored during different driving conditions, the OBD II system is designed to run separate monitoring programs called Readiness Monitors. Many state Inspection and Maintenance (I/M) programs require that vehicles complete their Readiness Monitors prior to beginning an emissions test.
2. The current status of the Readiness Monitors can be seen by using the hand-held tester with version 9.0 software (or newer), or a generic OBD II Scan tool.
3. To view the Readiness Monitor status using the hand-held tester, select "Monitor Status" from the Enhanced OBD II Menu.
4. A status of "complete" indicates that the necessary conditions have been met to run the performance tests for the related Readiness Monitor.
5. The Readiness Monitor will be reset to "incomplete" if: ECM has lost power (battery or fuse). DTCs have been cleared. The conditions for running the Readiness Monitor have not been met.
6. In the event that any Readiness Monitor shows "incomplete," follow the appropriate Readiness Monitor Drive Pattern to active the monitor and change the readiness status to "complete."

Note. These drive patterns represent the fastest method to satisfy all necessary conditions which allow the specific readiness monitor to complete. In the event that the drive pattern must be interrupted (possibly due to traffic conditions or other factors) the drive pattern can be resumed, and in most cases, the readiness monitor will still set to "complete". To ensure rapid completion of readiness monitors, avoid sudden changes in vehicle load and speed (driving up and down hills and/or sudden acceleration).

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1. CATALYST MONITOR Preconditions The monitor will not run unless: MIL is OFF. Engine Coolant Temperature (EOT) is 75°C (167°F) or greater. Intake Air Temperature (IAT) is -10°C (14°F) or greater. NOTE: The readiness test can be completed in cold ambient conditions (less than -10°C / 14°F), if the drive pattern is repeated a second time after cycling the ignition off. Drive Pattern Connect the OBD II scan tool to the DLC3 to check monitor status and preconditions. Drive the vehicle at 64 to 88 km/h (40 to 55 mph) for approximately for 3 minutes. NOTE: Drive with smooth throttle operation and avoid sudden acceleration. If IAT is less than 10°C (50°F) when engine was started, drive the vehicle at 64 to 88 km/h (40 to 55 mph) for additional 4 minutes. Drive the vehicle at 56 to 72 km/h (35 to 45 mph) for approximately 7 minutes. NOTE: Drive with smooth throttle operation and avoid sudden deceleration as much as possible with the throttle fully closed. If readiness status dose not switch to complete, make sure that the preconditions are met and the ignition switch is turned OFF and then repeat steps (2) and (3). Release pressure in the fuel tank by removing and then reinstalling the fuel tank cap. Start the engine and immediately begin driving as directed.
2. EVAP MONITOR NOTE: A cold soak must be performed prior to conducting the drive pattern to complete the Internal Pressure Readiness Monitor. Cold Soak Preconditions The monitor will not run unless: MIL is OFF Fuel level is approximately 1/2 to 3/4 Altitude is 2,400 m (7,800 feet) or less Cold Soak Procedure Let the vehicle cold soak for 8 hours or until the difference between IAT and ECT becomes less than 7°C (13°F) HINT: Example 1 ECT = 24°C (75°F) IAT = 16°C (60°F) Difference between ECT and IAT is 8°C (15°F) --> The monitor will not run because difference between ECT and IAT is greater than 7°C (13°F) Example 2 ECT = 21°C (70°F) IAT = 20°C (68°F) Difference between ECT and IAT is 1°C (2°F) --> The monitor will run because difference between ECT and IAT is less than 7°C (13°F) Preconditions The monitor will not run unless: MIL is OFF Fuel level is approximately 1/2 to 3/4 Altitude is 2,400 m (7,800 feet) or less Engine Coolant Temperature (EOT) is between 4.4°C and 35°C (40°F and 95°F) Intake Air Temperature (IAT) is between 4.4°C and 35°C (40°F and 95°F) Cold Soak Procedure has been completed Before starting the engine, the difference between ECT and IAT must be less than 7°C (13°F) HINT: Example 1 ECT = 24°C (75°F) IAT = 16°C (60°F) Difference between ECT and IAT is 8°C (15°F) --> The monitor will not run because difference between ECT and IAT is higher than 7°C (13°F) Example 2 ECT = 21°C (70°F) IAT = 20°C (68°F) Difference between ECT and IAT is 1 °C (2°F) --> The monitor will run because difference between ECT and IAT is less than 7°C (13°F) The readiness test can be completed in cold ambient conditions (less than 4.4°C / 40°F) and/or at high altitudes (more than 2,400 m / 7,800 feet) if the drive pattern is repeated a second time after cycling the ignition off. Drive Pattern Connect the OBD II scan tool to DLC3 to check monitor status and preconditions (refer to "a"). Release pressure in fuel tank by removing the fuel tank cap and then reinstalling it. Start the engine and allow it to idle until ECT becomes 75°C (167°F) or higher. Run the engine at 3,000 RPM for about 10 seconds. Allow the engine to idle with the A/C ON (to create slight load) for 15 to 50 minutes. NOTE: If the vehicle is not equipped with A/C put a slight load on the engine by doing the following: Securely set the parking brake. Block the drive wheels with wheel chocks. Allow the vehicle to idle in drive for 15 to 50 minutes.
3. OXYGEN SENSOR MONITOR Preconditions The monitor will not run unless: MIL is OFF Drive Pattern Connect the OBD II scan tool to DLC3 to check monitor status and preconditions (refer to step "a"). Start the engine and allow it to idle for 2 minutes or more. Drive the vehicle at 40 km/h (25 mph) or more for at least 50 seconds. Stop the vehicle and allow the engine to idle for 40 seconds or more. Perform steps (3) and (4) ten times. Check the status of the readiness monitor on the scan tool display. If readiness status did not switch to complete, ensure preconditions are met, turn the ignition off and then repeat steps (1) and (5).
4. OXYGEN SENSOR HEATER MONITOR Preconditions The monitor will not run unless: MIL is OFF Drive Pattern Connect the OBD II scan tool to the DLC3 to check monitor status and preconditions (refer to step "a"). Start the engine and allow it to idle for 500 seconds or more. Drive the vehicle at 40 km/h (25 mph) or more at least 2 minutes. Check the status of the readiness monitor on the scan tool display. If readiness status did not switch to complete, ensure the preconditions are met, turn the ignition off and then repeat steps (2) and (3).

TYPICAL MALFUNCTION THRESHOLDS

TYPICAL MALFUNCTION THRESHOLDS

Scheme 545

MONITOR RESULT

The detailed information is described in "checking monitor status" (see pre-check ).

1. TID (TEST IDENTIFICATION) IS ASSIGNED TO EACH EMISSION-RELATED COMPONENT.
2. TLT (TEST LIMIT TYPE): IF TLT IS 0, THE COMPONENT IS MALFUNCTIONING WHEN THE TEST VALUE IS HIGHER THAN THE TEST LIMIT. IF TLT IS 1, THE COMPONENT IS MALFUNCTIONING WHEN THE TEST VALUE IS LOWER THAN THE TEST LIMIT.
3. CID (COMPONENT IDENTIFICATION) IS ASSIGNED TO EACH TEST VALUE.
4. UNIT CONVERSION IS USED TO CALCULATE THE TEST VALUE INDICATED ON GENERIC OBD SCAN TOOLS.

TID $04: HO2S HEATER

H02S HEATER MALFUNCTION CHECK

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TYPICAL ENABLING CONDITIONS

TYPICAL ENABLING CONDITIONS

TYPICAL MALFUNCTION THRESHOLDS

COMPONENT OPERATING RANGE

COMPONENT OPERATING RANGE

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TYPICAL MALFUNCTION THRESHOLDS

TYPICAL ENABLING CONDITIONS

TYPICAL MALFUNCTION THRESHOLDS

COMPONENT OPERATING RANGE

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TYPICAL ENABLING CONDITIONS

TYPICAL MALFUNCTION THRESHOLDS

COMPONENT OPERATING RANGE

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TYPICAL MALFUNCTION THRESHOLDS

COMPONENT OPERATING RANGE

TYPICAL ENABLING CONDITIONS

TYPICAL MALFUNCTION THRESHOLDS

COMPONENT OPERATING RANGE

FAIL SAFE

If the ETCS (Electronic Throttle Control System) has a malfunction, the ECM cuts off current to the throttle control motor. The throttle control valve returns to a predetermined opening angle (approximately 16°) by the force of the return spring. The ECM then adjusts the engine output by controlling the fuel infection (intermittent fuel-cut) and ignition timing in accordance with the accelerator pedal opening angle to enable the vehicle to continue at a minimum speed.

If the accelerator pedal is depressed firmly and slowly, the vehicle can be driven slowly.

If a "pass" condition is detected and then the ignition switch is turned OFF, the fail-safe operation will stop and the system will return to normal condition.

Scheme 551

If the Electronic Throttle Control System (ETCS) has a malfunction, the ECM cuts off current to the throttle control motor. The throttle control valve returns to a predetermined opening angle (approximately 16°) by the force of the return spring. The ECM then adjusts the engine output by controlling the fuel infection (intermittent fuel-cut) and ignition timing in accordance with the accelerator pedal opening angle to enable the vehicle to continue at a minimum speed.

If the accelerator pedal is depressed firmly and slowly, the vehicle can be driven slowly.

If a "pass" condition is detected and then the ignition switch is turned OFF, the fail-safe operation will stop and the system will return to normal condition.

Scheme 552

TYPICAL ENABLING CONDITIONS

TYPICAL MALFUNCTION THRESHOLDS

TYPICAL MALFUNCTION THRESHOLDS

TYPICAL MALFUNCTION THRESHOLDS

The detailed information is described in "CHECKING MONITOR STATUS" (see PRE-CHECK ).

1. TID (Test Identification) is assigned to each emission-related component.
2. TLT (Test Limit Type): If TLT is 0, the component is malfunctioning when the test value is higher than the test limit. If TLT is 1, the component is malfunctioning when the test value is lower than the test limit.
3. CID (Component Identification) is assigned to each test value.
4. Unit Conversion is used to calculate the test value indicated on generic OBD scan tools.

TID $08: Thermostat

THERMOSTAT MALFUNCTION CHECK

TYPICAL MALFUNCTION THRESHOLDS

COMPONENT OPERATING RANGE

COMPONENT OPERATING RANGE

TYPICAL MALFUNCTION THRESHOLDS

COMPONENT OPERATING RANGE

COMPONENT OPERATING RANGE

TYPICAL MALFUNCTION THRESHOLDS

CONFIRMATION DRIVING PATTERN

1. Connect the hand-held tester to the DLC3.
2. Record DTC and the freeze frame data.
3. Use the hand-held tester to set to the check mode (see «PRE-CHECK»(ref-181813-S00378289582005080400000) ).
4. Read the value on the misfire counter for each cylinder when idling. If the value is displayed on the misfire counter, skip the following procedure of confirmation driving.
5. Drive the vehicle several times with the engine speed, load and its surrounding range shown with ENGINE SPD, CALC LOAD in the freeze frame data or MISFIRE RPM, MISFIRE LOAD in the DATA LIST. If you have no hand-held tester, turn the ignition switch OFF after the symptom is simulated once. Then repeat the simulation process again. HINT: In order to memorize the DTC of misfire, it is necessary to drive around MISFIRE RPM, MISFIRE LOAD in the DATA LIST for the following period of time. Take care not to turn the ignition switch OFF. Turning the ignition switch OFF switches the diagnosis system from check mode to normal mode. So all DTCs, etc., are erased. ENGINE SPEED TIME Engine Speed Time Idling 3 minutes 30 seconds or more 1,000 rpm 3 minutes or more 2,000 rpm 1 minute 30 seconds or more 3,000 rpm 1 minute or more
6. Check if there is misfire and DTC and the freeze frame data. Record the DTC's, freeze frame date and misfire counter date.
7. Turn the ignition switch OFF and wait at least 5 seconds.

COMPONENT OPERATING RANGE

TYPICAL MALFUNCTION THRESHOLDS

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TYPICAL MALFUNCTION THRESHOLDS

The detailed information is described in "CHECKING MONITOR STATUS" (see PRE-CHECK ).

1. TID (Test Identification) is assigned to each emission-related component.
2. TLT (Test Limit Type): If TLT is 0, the component is malfunctioning when the test value is higher than the test limit. If TLT is 1, the component is malfunctioning when the test value is lower than the test limit.
3. CID (Component Identification) is assigned to each test value.
4. Unit Conversion is used to calculate the test value indicated on generic OBD scan tools.

TID $01: Catalyst- Using Front HO2S and Rear HO2S

TEST VALUE DESCRIPTION

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1. Connect the hand-held tester to the DLC3, or connect the probe of the oscilloscope between terminals OXL1, OXL2, OXR1, OXR2 and E1 of the ECM connector.
2. Start the engine and warm it up with all accessories switched OFF until engine coolant temperature is stable.
3. Race the engine at 2,500 - 3,000 RPM for about 3 minutes.
4. After confirming that the waveform of the heated oxygen sensor (bank 1, 2 sensor 1 (OX1A, OX2A)), oscillate around 0.5 V during feedback to the ECM, check the waveform of the heated oxygen sensor (bank 1, 2 sensor 2 (OX1 B, OX2B)).

HINT

If there is a malfunction in the system, the waveform of the heated oxygen sensor (bank 1, 2 sensor 2 (OX1B, OX2B)) is almost the same as that of the heated oxygen sensor (bank 1, 2 sensor 1 (OX1A, OX2A)) on the left.

There are some cases where, even though a malfunction exists, the MIL may either light up or not light up.

Scheme 556

EVAP VSV stuck close (P0441)

TYPICAL MALFUNCTION THRESHOLDS

EVAP VSV stuck open (P0441)

EVAP VSV STUCK OPEN (P0441) MALFUNCTION

CCV stuck close (P0446)

CCV STUCK CLOSE (P0446) MALFUNCTION THRESHOLD

CCV stuck open (P0446)

CCV STUCK OPEN (P0446) MALFUNCTION THRESHOLD

EVAP 0.04 inch leak (P0442)

EVAP 0.04 INCH LEAK (P0442) MALFUNCTION THRESHOLD

EVAP 0.02 inch leak (P0456)

EVAP (0.02 INCH LEAK P0456) MALFUNCTION THRESHOLD

EVAP gross leak (P0455)

EVAP GROSS LEAK (P0455) MALFUNCTION THRESHOLD

The detailed information is described in "CHECKING MONITOR STATUS" (see PRE-CHECK ).

1. TID (Test Identification) is assigned to each emission-related component.
2. TLT (Test Limit Type): If TLT is 0, the component is malfunctioning when the test value is higher than the test limit. If TLT is 1, the component is malfunctioning when the test value is lower than the test limit.
3. CID (Component Identification) is assigned to each test value.
4. Unit Conversion is used to calculate the test value indicated on generic OBD scan tools.

TID $02: EVAP - LEVII Vacuum Monitor

EVAP - LEVII VACUUM MONITOR RESULT

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First Trip Procedure

1. Vehicle must be cold, ambient temperature approximately between 50°F - 95°F.
2. Intake Air Temperature (IAT) and Engine Coolant Temperature (ECT) sensor almost same value.
3. Clear DTC's. Disconnecting the battery terminals or EFI fuse. Readiness tests will show INCMPL (incomplete).
4. Drive the vehicle according to LA#4 drive cycle. Note the state of Readiness Tests. They will change to COMPL as the evaluation monitors operate and if the system passes. This procedure may take approximately 20 minutes or more.

Scheme 559

Note. Do not shut off the engine - the results will be invalid. Pass Condition - No Problem Found by the ECM

If the EVAP evaluation monitor shows COMPL, go to the Non-Continuous Test screen.

Note. Do not shut off the engine - the results will be invalid.

Scheme 560

1. To get there, go to Advanced OBD II, Onboard Tests, Non-continuous Tests.
2. If all of the tests in the time $02 category Tests show Pass, the evaluation monitor has operated and no problem was detected.

Scheme 561

Fail Condition - Problem Detected by the ECM

If the EVAP evaluation monitor shows INCMPL, go to the Non-Continuous Test screen.

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1. If all Tests show Pass, the following may have occurred. The EVAP evaluation monitor did not operate. The EVAP evaluation monitor did not finish. The ECM withheld judgement.
2. If one or more of the tests in the time $02 category show Fail, the EVAP evaluation monitor did operate and the ECM detected a problem.
3. Go to Continuous Tests screen. This is the only place DTC's are listed for the first trip.

Note. The DTC listed may not be valid. A second trip is needed to confirm the DTC.

Scheme 564

Second Trip Procedure

1. Vehicle must be cold, ambient temperature approximately between 50°F - 95°F.
2. Go to Readiness Tests screen.
3. Drive the vehicle according to LA#4 drive cycle. Note the state of EVAP evaluation monitor. This procedure may take approximately 20 minutes or more.

Note. Do not shut off the engine - the results will be invalid.

Scheme 565

If Readiness Tests changes to COMPL, the EVAP evaluation monitor has operated. Check for any stored DTC's.

1. If a DTC has stored, the problem has been detected and confirmed by the ECM.
2. If no DTC was found, the EVAP monitor operated but no problem was detected.

Scheme 566

TYPICAL MALFUNCTION THRESHOLDS

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1. Check operation of speedometer. CHECK: Drive the vehicle and check if the operation of the speedometer in the combination meter is normal. HINT: The vehicle speed is operating normally if the speedometer display is normal. NG: Check speedometer circuit. See combination meter troubleshooting (See «COMBINATION METER»(ref-182158) ). OK: Go To Next Step
2. Check voltage between terminal SPD and E1 of ECM connector. PREPARATION: Remove the glove compartment door (see «ENGINE CONTROL MODULE (ECM)»(ref-181796-S23719593312006080100000) ). Shift the gear to neutral. Jack up the rear wheel on one side. Turn the ignition switch ON. CHECK: Measure the voltage between the specified terminal of the E4 and E5 ECM connector when the wheel is turned slowly. OK: TESTER CONNECTION SPECIFIED CONDITION Tester Connection Specified Condition SPD (E4-17) - E1 (E5-1) Generated intermittently HINT: The output voltage should fluctuate up and down similarly to the diagram on the left when the wheel is turned slowly. NG: Check and repair harness and connector between combination meter and ECM. OK: Replace ECM (See «ENGINE CONTROL MODULE (ECM)»(ref-181796-S23719593312006080100000) ).

TYPICAL MALFUNCTION THRESHOLDS

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1. Check EFI No. 1 fuse of engine room J/B. PREPARATION: Remove the EFI No. 1 fuse from the engine room J/B. CHECK: Check the continuity of the EFI No. 1 fuse. OK: Continuity NG: Check for short in all harness and components connected to EFI No. 1 fuse. OK: Go To Next Step
2. Check voltage between terminal BATT and E1 of ECM connector. CHECK: Measure the voltage between terminals of the E3 and E5 ECM connector. OK: TESTER CONNECTION SPECIFIED CONDITION Tester Connection Specified Condition BATT (E3-3) - E1 (E5-1) 9 to 14 V OK: Check for intermittent problems (See «PRE-CHECK»(ref-181813-S00378289582005080400000) ). NG: Go To Next Step
3. Check wire harness and connector between ECM, EFI No. 1 fuse and battery. NG: Repair or replace harness or connector. OK: Check and replace engine room J/B.

TYPICAL MALFUNCTION THRESHOLDS

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If the ETCS (Electronic Throttle Control System) has a malfunction, the ECM cuts off current to the throttle control motor. The throttle control valve returns to a predetermined opening angle (approximately 16°) by the force of the return spring. The ECM then adjusts the engine output by controlling the fuel infection (intermittent fuel-cut) and ignition timing in accordance with the accelerator pedal opening angle to enable the vehicle to continue at a minimum speed.

If the accelerator pedal is depressed firmly and slowly, the vehicle can be driven slowly.

If a "pass" condition is detected and then the ignition switch is turned OFF, the fail-safe operation will stop and the system will return to normal condition.

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Scheme 581

1. Check throttle actuator. PREPARATION: Disconnect the throttle actuator connector. CHECK: Measure the resistance between terminals of the throttle motor. OK: TESTER CONNECTION SPECIFIED CONDITION Tester Connection Specified Condition M+ - M- 0.3 to 100 ohm (20°C (68°F)) NG: Replace throttle body (See «THROTTLE BODY»(ref-181796-S13923946182006080100000) ). OK: Go To Next Step
2. Check for open and short in harness and connector between throttle control motor and ECM. PREPARATION: Disconnect the T14 throttle control motor and sensor connector. Disconnect the E5 ECM connector. CHECK: Measure the resistance between the wire harness side connectors. OK: TESTER CONNECTION SPECIFIED CONDITION Tester Connection Specified Condition M+ (T14-2) - M+ (E5-3) Below 1 ohm M- (T14-1) - M- (E5-2) Below 1 ohm M+ (T14-2) or M+ (E5-3) - Body ground 10 kohm or higher M- (T14-1) or M- (E5-2) - Body ground 10 kohm or higher NG: Repair or replace harness or connector. OK: Go To Next Step
3. Visually check throttle valve. CHECK: Check between the throttle valve and the housing for foreign objects. Also, check if the valve can open and close smoothly. NG: Remove foreign object and clean throttle body. OK: Replace ECM (See «ENGINE CONTROL MODULE (ECM)»(ref-181796-S23719593312006080100000) ).

If the ETCS has a malfunction, the ECM cuts off current to the throttle control motor. The throttle control valve returns to a predetermined opening angle (approximately 16°) by the force of the return spring. The ECM then adjusts the engine output by controlling the fuel infection (intermittent fuel-cut) and ignition timing in accordance with the accelerator pedal opening angle to enable the vehicle to continue at a minimum speed. If the accelerator pedal is depressed firmly and slowly, the vehicle can be driven slowly.

If a "pass" condition is detected and then the ignition switch is turned OFF, the fail-safe operation will stop and the system will return to normal condition.

Scheme 582

Scheme 583

TYPICAL MALFUNCTION THRESHOLDS

If the ETCS has a malfunction, the ECM cuts off current to the throttle control motor. The throttle control valve returns to a predetermined opening angle (approximately 16°) by the force of the return spring. The ECM then adjusts the engine output by controlling the fuel infection (intermittent fuel-cut) and ignition timing in accordance with the accelerator pedal opening angle to enable the vehicle to continue at a minimum speed. If the accelerator pedal is depressed firmly and slowly, the vehicle can be driven slowly.

If a "pass" condition is detected and then the ignition switch is turned OFF, the fail-safe operation will stop and the system will return to normal condition.

Scheme 584

Scheme 585

TYPICAL MALFUNCTION THRESHOLDS

COMPONENT OPERATING RANGE

Scheme 586

Scheme 587

If the ETCS has a malfunction, the ECM cuts off current to the throttle control motor. The throttle control valve returns to a predetermined opening angle (approximately 16°) by the force of the return spring. The ECM then adjusts the engine output by controlling the fuel infection (intermittent fuel-cut) and ignition timing in accordance with the accelerator pedal opening angle to enable the vehicle to continue at a minimum speed. If the accelerator pedal is depressed firmly and slowly, the vehicle can be driven slowly.

If a "pass" condition is detected and then the ignition switch is turned OFF, the fail-safe operation will stop and the system will return to normal condition.

Scheme 588

TYPICAL ENABLING CONDITIONS

TYPICAL MALFUNCTION THRESHOLDS

The accelerator pedal position sensor has two (main and sub) sensor circuits. If a malfunction occurs in either of the sensor circuits, the ECM detects the abnormal signal voltage difference between the two sensor circuits and switches to limp mode. In limp mode, the remaining circuit is used to calculate the accelerator pedal opening to allow the vehicle to continue driving.

If both circuits malfunction, the ECM regards the opening angle of the accelerator pedal to be fully closed. In this case, the throttle valve will remain closed as if the engine is idling.

If a "pass" condition is detected and then the ignition switch is turned OFF, the fail-safe operation will stop and the system will return to normal condition.

Scheme 589

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Scheme 591

COMPONENT OPERATING RANGE

Scheme 592

The accelerator pedal position sensor has two (main and sub) sensor circuits. If a malfunction occurs in either of the sensor circuits, the ECM detects the abnormal signal voltage difference between the two sensor circuits and switches to limp mode. In limp mode, the remaining circuit is used to calculate the accelerator pedal opening to allow the vehicle to continue driving.

If both circuits malfunction, the ECM regards the opening angle of the accelerator pedal to be fully closed. In this case, the throttle valve will remain closed as if the engine is idling.

If a "pass" condition is detected and then the ignition switch is turned OFF, the fail-safe operation will stop and the system will return to normal condition.

Scheme 593

Scheme 594

TYPICAL MALFUNCTION THRESHOLDS