Engine Control System (2ZR-FE) (Diagnostic Codes (P043E-P1605): Overview Toyota Corolla X рестайлинг

DESCRIPTION

The description can be found in the EVAP (Evaporative Emission) System. Refer to DESCRIPTION .

HINT

Unit expressions

1. [kPa-a (mmHg-a)] denotes absolute pressure.
2. [kPa-g (mmHg-g)] denotes gauge pressure (relative pressure).
3. On the Techstream, choose the unit of measurement according to the inspection procedure.

MONITOR DESCRIPTION

5 hours* after the ignition switch is turned off, the leak detection pump creates negative pressure (vacuum) in the EVAP system. The ECM monitors for leaks and actuator malfunctions based on the EVAP pressure.

HINT

*: If the engine coolant temperature is not below 35°C (95°F) 5 hours after the ignition switch is turned off, the monitor check starts 2 hours later. If it is still not below 35°C (95°F) 7 hours after the ignition switch is turned off, the monitor check starts 2.5 hours later.

*: If only a small amount of fuel is in the fuel tank, it takes longer for the EVAP pressure to stabilize.

Scheme 301

The leak detection pump creates negative pressure through the reference orifice (in operation B and E). When the system is normal, the EVAP pressure is between 724 to 752 mmHg* and saturated within a minute. If not, the ECM interprets this as a malfunction. The ECM will illuminate the MIL and set DTC if this malfunction is detected in consecutive drive cycles.

*: Typical value.

Scheme 302

The description can be found in the EVAP (Evaporative Emission) System. Refer to DESCRIPTION .

HINT

Unit expressions

1. [kPa-a (mmHg-a)] denotes absolute pressure.
2. [kPa-g (mmHg-g)] denotes gauge pressure (relative pressure).
3. On the Techstream, chose the unit of measurement according to the inspection procedure.

The two monitors, Key-Off and Purge Flow, are used to detect malfunctions relating to DTC P0441. The Key-Off monitor is initiated by the ECM internal timer, known as the soak timer, 5 hours* after the ignition off. The purge flow monitor runs while the engine is running.

Scheme 303

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Scheme 305

1. KEY-OFF MONITOR 5 hours* after the ignition switch is turned off, the leak detection pump creates negative pressure (vacuum) in the EVAP system. The ECM monitors for leaks and actuator malfunctions based on the EVAP pressure. HINT: *: If the engine coolant temperature is not below 35°C (95°F) 5 hours after the ignition switch is turned off, the monitor check starts 2 hours later. If it is still not below 35°C (95°F) 7 hours after the ignition switch is turned off, the monitor check starts 2.5 hours later. Sequence Operation Description Duration - ECM activation The key-off monitor is activated by soak timer 5, 7 or 9.5 hours after ignition switch turned off. - A Atmospheric pressure measurement Vent valve is turned OFF (vent) and the EVAP system pressure is measured by ECM in order to register atmospheric pressure. If pressure in EVAP system is not between 70 kPa-a and 110 kPa-a (525 mmHg-a and 825 mmHg-a), the ECM cancels EVAP system monitor. 60 seconds B First reference pressure measurement In order to determine reference pressure, the leak detection pump creates negative pressure (vacuum) through reference orifice and then ECM checks if the leak detection pump and vent valve operate normally. 60 seconds C EVAP system pressure measurement Vent valve turned ON (closed) to shut the EVAP system. Negative pressure (vacuum) created in the EVAP system, and EVAP system pressure then measured. The measured value is memorized as it will be used in the leak check. If the EVAP pressure does not stabilize within 15 minutes, the ECM cancels EVAP system monitor. 15 minutes* D Purge VSV monitor Purge VSV is opened and then the EVAP system pressure is measured by the ECM. A large increase indicates normality. 10 seconds E Second reference pressure measurement After a second reference pressure measurement, the leak check is performed by comparing the first and second reference pressure. If stabilized system pressure is higher than second the reference pressure, the ECM determines that the EVAP system is leaking. 60 seconds - Final check Atmospheric pressure is measured and then the monitor result is recorded by the ECM. - *: If only a small amount of fuel is in the fuel tank, it takes longer for the EVAP pressure to stabilize. Purge VSV stuck open In operation C, the leak detection pump creates negative pressure (vacuum) in the EVAP system. The EVAP system pressure is then measured by the ECM using the canister pressure sensor. If the stabilized system pressure is higher than [second reference pressure x 0.2], the ECM interprets this as the purge VSV (Vacuum Switching Valve) being stuck open. The ECM illuminates the MIL and sets the DTC (2 trip detection logic). Purge VSV stuck closed In operation D, the canister pressure sensor measures the EVAP system pressure. The pressure measurement for the purge VSV monitor is begun when the purge VSV is turned ON (open) after the EVAP leak check. When the measured pressure indicates an increase of 0.3 kPa-g (2.25 mmHg-g) or more, the purge VSV is functioning normally. If the pressure does not increase, the ECM interprets this as the purge VSV being stuck closed. The ECM illuminates the MIL and sets the DTC (2 trip detection logic).
2. PURGE FLOW MONITOR The purge flow monitor consists of two monitors. The 1st monitor is conducted every time and the 2nd monitor is activated if necessary.

1. The 1st monitor While the engine is running and the purge VSV is ON (open), the ECM monitors the purge flow by measuring the EVAP pressure change. If negative pressure is not created, the ECM begins the 2nd monitor.
2. The 2nd monitor The vent valve is turned ON (closed) and the EVAP pressure is then measured. If the variation in the pressure is less than 0.4 kPa-g (3.0 mmHg-g), the ECM interprets this as the purge VSV being stuck closed, illuminates the MIL and sets DTC P0441 (2 trip detection logic).

Atmospheric pressure check

In order to ensure reliable malfunction detection, the variation between the atmospheric pressures, before and after the purge flow monitor is performed, is measured by the ECM.

HINT

This DTC P0443 is applicable to Mexico models only.

To reduce hydrocarbon emissions, evaporated fuel from the fuel tank is routed through a charcoal canister to the intake manifold for combustion in the cylinders.

The ECM changes the duty signals to the purge VSV so that the intake amount of hydrocarbon emissions is appropriate for the driving conditions (engine load, engine speed, vehicle speed, etc.) after the engine is warmed up.

Scheme 306

The description can be found in the EVAP (Evaporative Emission) System. Refer to DESCRIPTION .

HINT

Unit expressions

1. [kPa-a (mmHg-a)] denotes absolute pressure.
2. [kPa-g (mmHg-g)] denotes gauge pressure (relative pressure).
3. On the Techstream, choose the unit of measurement according to the inspection procedure.

Scheme 307

1. DTC P0451: Canister pressure sensor noise or fixed/flat If the canister pressure sensor voltage output fluctuates rapidly for 10 seconds, the ECM stops the EVAP system monitor. The ECM interprets this as noise from the canister pressure sensor, and stops the EVAP system monitor. The ECM then illuminates the MIL and sets the DTC. Alternatively, if the sensor voltage output does not change for 10 seconds, the ECM interprets this as the sensor being fixed/flat, and stops the monitor. The ECM then illuminates the MIL and sets the DTC. (Both malfunctions are detected by 2 trip detection logic.)
2. DTC P0452: Canister pressure sensor low pressure If the canister pressure sensor pressure is less than 42.11 kPa-a (315.83 mmHg-a), the ECM interprets this as an open or short circuit malfunction in the canister pressure sensor or its circuit, and stops the EVAP system monitor. The ECM then illuminates the MIL and sets the DTC (1 trip detection logic).
3. DTC P0453: Canister pressure sensor high pressure If the canister pressure sensor pressure is more than 123.761 kPa-a (928.208 mmHg-a), the ECM interprets this as an open or short circuit malfunction in the canister pressure sensor or its circuit, and stops the EVAP system monitor. The ECM then illuminates the MIL and sets the DTC (1 trip detection logic).

The description can be found in the EVAP (Evaporative Emission) System. Refer to DESCRIPTION .

HINT

Unit expressions

1. [kPa-a (mmHg-a)] denotes absolute pressure.
2. [kPa-g (mmHg-g)] denotes gauge pressure (relative pressure).
3. On the Techstream, choose the unit of measurement according to the inspection procedure.

5 hours* after the ignition switch is turned off, the leak detection pump creates negative pressure (vacuum) in the EVAP system. The ECM monitors for leaks and actuator malfunctions based on the EVAP pressure.

HINT

*: If the engine coolant temperature is not below 35°C (95°F) 5 hours after the ignition switch is turned off, the monitor check starts 2 hours later. If it is still not below 35°C (95°F) 7 hours after the ignition switch is turned off, the monitor check starts 2.5 hours later.

*: If only a small amount of fuel is in the fuel tank, it takes longer for the EVAP pressure to stabilize.

Scheme 308

1. (a) P0455: EVAP gross leak In operation C, the leak detection pump creates negative pressure (vacuum) in the EVAP system and the EVAP system pressure is measured. If the stabilized system pressure is higher than [second reference pressure x 0.2] (near atmospheric pressure), the ECM determines that the EVAP system has a large leak, illuminates the MIL and sets the DTC (2 trip detection logic).
2. (b) P0456: EVAP very small leak In operation C, the leak detection pump creates negative pressure (vacuum) in the EVAP system and the EVAP system pressure is measured. If the stabilized system pressure is higher than the second reference pressure, the ECM determines that the EVAP system has a small leak, illuminates the MIL and sets the DTC (2 trip detection logic).

The speed sensors detect the wheel speed and send the appropriate signals to the skid control ECU. The skid control ECU converts these wheel speed signals into a 4-pulse signal and outputs it to the ECM via the combination meter. The ECM determines the vehicle speed based on the frequency of these pulse signals.

Scheme 309

Automatic Transaxle Models

The ECM assumes that the vehicle is being driven when the vehicle speed sensor signal is being transmitted by the combination meter. If there is no signal from the combination meter, despite the ECM detecting the speed signal from the speed sensor NC, the ECM interprets this as a malfunction in the speed signal circuit. The ECM then illuminates the MIL and sets the DTC.

Manual Transaxle Models

The ECM assumes that the vehicle is being driven when the idle fuel-cut operation* is being executed. If there is no signal from the vehicle speed sensor, despite these conditions being met, the ECM interprets this as a malfunction in the speed signal circuit. The ECM then illuminates the MIL and sets the DTC.

*: Idle fuel-cut is executed when the throttle valve is fully closed and engine speed is over 2500 RPM.

The stop light switch is a duplex system that transmits two signals: STP and ST1-. These two signals are used by the ECM to monitor whether or not the brake system is working properly. If the signals, which indicate the brake pedal is being depressed and released, are detected simultaneously, the ECM interprets this as a malfunction in the stop light switch and sets the DTC.

HINT

The normal signal conditions are as shown in the table below.

1. [OFF] denotes ground potential.
2. [ON] denotes battery potential (+B).
3. On the Techstream, the Data List items Stop Light Switch and ST1 are both ON when the brake pedal is depressed because the characteristics of ST1 indication are the opposite of the characteristics of Stop Light Switch indication.

Scheme 310

Scheme 311

The idle speed is controlled by the electronic throttle control system. The electronic throttle control system is comprised of: 1) the one valve type throttle body; 2) a throttle actuator, which operates the throttle valve; 3) a throttle position sensor, which detects the opening angle of the throttle valve; 4) an accelerator pedal position sensor, which detects the accelerator pedal position; and 5) the ECM, which controls the electronic throttle control system. Based on the target idle speed, the ECM controls the throttle actuator to provide the proper throttle valve opening angle.

The ECM monitors the idling speed and idling air flow volume to conduct Idle Speed Control (ISC). The ECM determines that the ISC system is malfunctioning if either of the following conditions is met

1. The difference between the target engine idling speed and actual engine idling speed exceeds the threshold and the IAC flow rate learned value is stuck at the upper or lower limit for 5 seconds or more.
2. After driving at a vehicle speed of 6.25 mph (10 km/h) or more, the difference between the target and actual engine idling speed exceeds the threshold 5 times or more during a driving cycle, and then the system determines that the IAC flow rate learned value is stuck at the upper or lower limit, or that the IAC flow rate learned value has been changed by an amount that exceeds the threshold.

Scheme 312

This monitor will run when the engine is started at an engine coolant temperature of -10 to 50°C (14 to 122°F). The DTC can be set after the engine idles for 13 seconds (2 trip detection logic).

The DTC is designed to monitor the idle air control at cold start. When the engine is started at an engine coolant temperature of lower than 50°C (122°F), the ECM measures the accumulated mass air flow at idle. If it does not reach the specified level within 10 seconds, the ECM interprets this as a malfunction. The MIL is illuminated and a DTC is set when the malfunction is detected in consecutive driving cycles (2 trip detection logic).

The electronic throttle control system controls the idle speed. The electronic throttle control system operates the throttle actuator to open and close the throttle valve, and adjusts the intake air amount to achieve the target idle speed.

Note. When the negative battery terminal is disconnected during inspection or repairs, the idle speed control (ISC) learned values are cleared. Idle speed control learning needs to be performed before this DTC can be stored. To perform idle speed control learning, the engine must be warmed up by allowing it to idle for 5 minutes. For idle speed control learning to be successful, when the engine is started to warm it up, there must be at least 10 seconds of idling with the coolant temperature below 30°C before allowing it to continue running for the 5 minute learning period.

HINT

The idle speed control learning is performed when the engine is warmed up and has been idling for 5 minutes.

Scheme 313

This monitor will run when the engine is started at an engine coolant temperature of -10 to 50°C (14 to 122°F). The DTC is stored after the engine idles for 13 seconds (2 trip detection logic).

The DTC is designed to monitor the ignition timing at cold start. When the engine is started at an engine coolant temperature of below 50°C (122°F), the ECM checks the ignition timing during engine idling. If the ignition timing advances beyond the specified level within 10 seconds, the ECM interprets this as a malfunction. The MIL is illuminated and a DTC is stored when the malfunction is detected in consecutive driving cycles (2 trip detection logic).

Note. When the cable is disconnected from the negative (-) battery terminal during inspections or repairs, the idle speed control learned values are cleared. This DTC cannot be stored with the idle speed control learned values cleared.

HINT

The idle speed control learning is performed when the engine is warmed up and has been idling for 5 minutes.

Scheme 314

The battery supplies electricity to the ECM even when the ignition switch is off. This power allows the ECM to store data such as DTC history, freeze frame data and fuel trim values. If the battery voltage falls below a minimum level, the memory is cleared and the ECM determines that there is a malfunction in the power supply circuit. The next time the engine is started, the ECM illuminates the MIL and sets the DTC.

HINT

If DTC P0560 is set, the ECM does not store other DTCs or the data stored in the ECM may be partly erased.

The ECM continuously monitors its own internal memory status, internal circuits, and output signals transmitted to the throttle actuator. This self-check insures that the ECM is functioning properly. If any malfunction is detected, the ECM sets the appropriate DTC and illuminates the MIL.

The ECM memory status is diagnosed by internal mirroring of the main CPU and the sub CPU to detect Random Access Memory (RAM) errors. The two CPUs also perform continuous mutual monitoring. The ECM illuminates the MIL and sets a DTC if: 1) outputs from the two CPUs are different or deviate from the standards, 2) the signals sent to the throttle actuator deviate from the standards, 3) a malfunction is found in the throttle actuator supply voltage, and 4) any other ECM malfunction is found.

The ECM continuously monitors its internal memory status. This self-check ensures that the ECM is functioning properly. It is diagnosed by internal "mirroring" of the main CPU and sub CPU to detect Random Access Memory (RAM) errors. If outputs from these CPUs are different and deviate from the standards, the ECM will illuminate the MIL and set the DTC immediately.

The ECM continuously monitors its main and sub CPUs. This self-check ensures that the ECM is functioning properly. If outputs from the CPUs are different and deviate from the standards, the ECM will illuminate the MIL and set the DTC immediately.

The ECM continuously monitors its internal processors (CPUs) and heated oxygen sensor transistors. This self-check ensures that the ECM is functioning properly.

The main CPU and sub CPU of the ECM communicate with between each other. The main CPU monitors the communications and WDC pulses from the sub CPU. When the signal malfunctions below deviate, the DTC is stored.

The ECM monitors the input signals of the accelerator pedal position sensor No. 1. If the input signals and control signals deviate, the DTC is output.

The ECM monitors the input signals of the throttle position sensor No. 1 and stop light switch. When the ECM monitors the input signals of the throttle position sensor No. 1 and the STP signal of the stop light switch, if the input signals and control signals deviate, the DTC is stored.

While the engine is being cranked, battery voltage is applied to terminal STA of the ECM.

If the ECM detects the starter signal (STA signal) while the vehicle is being driven, it determines that there is a malfunction in the STA circuit. The ECM then illuminates the MIL and sets the DTC.

This monitor runs when the vehicle is driven at 12.43 mph (20 km/h) for over 20 seconds.

1. *1: Automatic transaxle models.
2. *2: Manual transaxle models.

Scheme 315

Scheme 316

The ECM monitors its internal operation and stores this DTC when it detects an internal malfunction.

The ECM monitors its internal operation. If there is an internal operation malfunction, the ECM illuminates the MIL and stores a DTC.

DTC P0630 is set when the Vehicle Identification Number (VIN) is not stored in the Engine Control Module (ECM) or the input VIN is not accurate. Input the VIN with the Techstream.

The ECM monitors the output voltage to the throttle actuator. This self-check ensures that the ECM is functioning properly. The output voltage is usually 0 V when the ignition switch is turned off. If the output voltage is 7 V or more when the ignition switch is turned off, the ECM will illuminate the MIL and set the DTC the next time the ignition switch is turned to ON.

The purpose of this circuit is to prevent the engine from stalling when brakes are suddenly applied while driving with the lock-up torque converter clutch on.

When the brake pedal is depressed, this switch sends a signal to the ECM. Then the ECM cancels the operation of the lock-up clutch while braking is in progress.

This DTC indicates that the stop light switch remains ON. When the stop light switch remains ON during "stop and go" driving, the ECM interprets this as a fault in the stop light switch and the MIL comes on and the ECM stores the DTC. The vehicle must stop (less than 1.86 mph [3 km/h]) and go (18.65 mph [30 km/h] or more) 5 times during 2 driving cycles, in order to detect a malfunction.

P1603

After starting the engine, this DTC is stored when the engine stops without the ignition switch being operated.

Using the Techstream, the conditions present when the DTC was stored can be confirmed by referring to the freeze frame data. Freeze frame data records engine conditions when a malfunction occurs. This information can be useful when troubleshooting.

It is necessary to check if the vehicle has ran out of fuel before performing troubleshooting, as this DTC is also stored when the engine stalls due to running out of fuel.

*1: for Automatic transaxle models

P1605

This DTC is stored if the engine speed drops below the set speed.

Using the Techstream, the conditions present when the DTC was stored can be confirmed by referring to the freeze frame data. Freeze frame data records engine conditions when a malfunction occurs. This information can be useful when troubleshooting.

It is necessary to check if the vehicle ran out of fuel before performing troubleshooting, as this DTC is also stored when idling is unstable due to running out of fuel.

*1: for Automatic transaxle models

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Scheme 318

1. Reference waveforms showing a normal cold engine start
2. Reference waveforms showing a normal warm engine start
3. Reference values when there is an air leak in the intake system during rough idling FREEZE FRAME DATA P1605 ROUGH IDLING Engine Current P1605: Rough Idling Time Freeze Frame Data Item Data1 Data2 Data3 Data4 Data5 Unit Engine Speed 647 649 586 378 182 RPM Calculate Load 26.2 26.2 29.1 42.6 58.6 % Vehicle Load 11.7 11.7 12.1 48.7 61.2 % MAF 2.87 2.87 2.87 6.23 3.04 gm/sec Atmosphere Pressure -0 -0 -0 -0 -0 psi (gauge) Coolant Temp 86 86 86 86 86 °C Intake Air 43 43 43 43 43 °C Battery Voltage 13.515 13.515 13.264 12.892 12.792 V Throttle Sensor Volt % 14.5 14.5 14.5 16.8 17.2 % Throttl Sensor #2 Volt % 46.2 46.2 46.2 48.4 49.2 % Throttle Sensor Position 0.0 0.0 0.0 0.0 0.0 % Throttle Motor DUTY 14.5 14.5 14.5 17.2 17.2 % Injector (Port) 2159 2161 2148 2190 2190 μs Injection Volume (Cylinder 1) 0.093 0.093 0.093 0.095 0.095 ml Fuel Pump/Speed Status ON ON ON ON ON EVAP (Purge) VSV 13.3 13.3 13.3 13.3 13.3 % Evap Purge Flow 2.9 2.9 2.9 3.2 3.2 % Purge Density Learn Value 0.891 0.891 0.891 0.891 0.891 EVAP System Vent Valve OFF OFF OFF OFF OFF EVAP Purge VSV OFF OFF OFF OFF OFF Purge Cut VSV Duty 8.5 8.5 8.5 8.5 8.5 % Target Air-Fuel Ratio 0.998 0.998 0.998 0.998 0.998 AF Lambda B1S1 0.999 0.997 1.001 1.038 1.118 AFS Voltage B1S1 3.258 3.242 3.284 3.521 3.715 V O2S B1S2 0.740 0.740 0.740 0.740 0.740 V Short FT #1 -1.563 -1.563 -1.563 -1.563 -1.563 % Long FT #1 6.250 6.250 6.250 6.250 6.250 % Total FT #1 0.054 0.054 0.054 0.054 0.054 Fuel System Status #1 CL CL CL CL CL IGN Advance 22.0 22.0 22.5 23.5 23.5 Deg Knock Feedback Value -1.5 -1.5 -1.5 -1.5 -1.5 °CA Knock Correct Learn Value 17.0 17.0 17.0 17.0 17.0 °CA Starter Signal Close Close Close Close Close Ambient Temperature 21 21 21 21 21 °C