Engine Control System (Diagnostic Codes (P0365-P1603): Overview Scion xD I

DESCRIPTION

The camshaft position sensor for exhaust camshaft (EV signal sensor) consists of a magnet and MRE element.

The exhaust camshaft has a timing rotor for camshaft position sensor. When the camshaft rotates, changes occur in the air gaps between the timing rotor and MRE element, which affect the magnet. As a result, the resistance of the MRE material fluctuates. The camshaft position sensor converts the camshaft rotation data to pulse signals, and uses the pulse signals to determine the camshaft angle, which it sends to the ECM. Then the ECM uses this data to control fuel injection time, injection timing and the Variable Valve Timing (VVT) system.

HINT

DTC P0365, P0367 and P0368 indicate a malfunction relating to the exhaust camshaft position sensor circuit (the wire harness between the ECM and exhaust camshaft position sensor, and the exhaust camshaft position sensor itself).

Reference: Inspection using an oscilloscope. Refer to DESCRIPTION

MONITOR DESCRIPTION

If no signal is transmitted by the exhaust camshaft position sensor despite the engine revolving, or the rotation of the exhaust camshaft and the crankshaft is not synchronized, the ECM interprets this as a malfunction of the sensor.

If the malfunction is not repaired successfully, the DTC is set 10 seconds after the engine is next started.

The ECM uses sensors mounted in front of and behind the Three-Way Catalytic Converter (TWC) to monitor its efficiency.

The first sensor, the Air Fuel Ratio (A/F) sensor, sends pre-catalyst information to the ECM. The second sensor, the Heated Oxygen (HO2) sensor, sends post-catalyst information to the ECM.

In order to detect any deterioration in the TWC, the ECM calculates the Oxygen Storage Capacity (OSC) of the TWC. This calculation is based on the voltage output of the HO2 sensor while performing active air-fuel ratio control.

The OSC value is an indication of the oxygen storage capacity of the TWC. When the vehicle is being driven with a warm engine, active air-fuel ratio control is performed for approximately 15 to 20 seconds. When it is performed, the ECM deliberately sets the air-fuel ratio to lean or rich levels. If a rich-lean cycle of the HO2 sensor is long, the OSC becomes greater. There is a direct correlation between the OSCs of the HO2 sensor and the TWC.

The ECM uses the OSC value to determine the state of the TWC. If any deterioration has occurred, it illuminates the MIL and sets the DTC.

HINT

1. Sensor 1 refers to the sensor closest to the engine assembly.
2. Sensor 2 refers to the sensor farthest away from the engine assembly.

Scheme 31

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

HINT

Unit expressions

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

5 hours* after the ignition switch is turned to 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 to 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 to 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 32

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 33

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

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 switch is turned to OFF. The purge flow monitor runs while the engine is running.

Scheme 34

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1. KEY-OFF MONITOR 5 hours* after the ignition switch is turned to 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 to 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 to OFF, the monitor check starts 2.5 hours later. Sequence Operation Description Duration - ECM activation Activated by soak timer 5, 7 or 9.5 hours after ignition switch turned to OFF. - A Atmospheric pressure measurement Vent valve turned OFF (vent) and EVAP system pressure measured by ECM in order to register atmospheric pressure. If pressure in EVAP system not between 70 kPa-a and 110 kPa-a (525 mmHg-a and 825 mmHg-a), ECM cancels EVAP system monitor. 60 seconds B First reference pressure measurement In order to determine reference pressure, leak detection pump creates negative pressure (vacuum) through reference orifice and then ECM checks if leak detection pump and vent valve operate normally. 60 seconds C EVAP system pressure measurement Vent valve turned ON (closed) to shut EVAP system. Negative pressure (vacuum) created in EVAP system, and EVAP system pressure then measured. Write down measured value as it will be used in leak check. If EVAP pressure does not stabilize within 15 minutes, ECM cancels EVAP system monitor. 15 minutes* D Purge VSV monitor Purge VSV opened and then EVAP system pressure measured by ECM. Large increase indicates normality. 10 seconds E Second reference pressure measurement After second reference pressure measurement, leak check performed by comparing first and second reference pressure. If stabilized system pressure higher than second reference pressure, ECM determines that EVAP system leaking. 60 seconds - Final check Atmospheric pressure measured and then monitoring result recorded by 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, and 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 conduction of the purge flow monitor, is measured by the ECM.

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

HINT

Unit expressions

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

Scheme 37

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 voltage low If the canister pressure sensor voltage output [pressure] is below 0.45 V [42.1 kPa-a (315.7 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 voltage high If the canister pressure sensor voltage output [pressure] is 4.9 V [123.8 kPa-a (928.5 mmHg-a)] or more, 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 .

5 hours* after the ignition switch is turned to 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 to 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 to 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 38

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 sensor detects the wheel speed and sends 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 39

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 indicated engine speed is 2000 to 5000 rpm and the engine load calculated by the ECM is more than a certain level or 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 2800 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 conditions are as shown in the table below. The signals can be read using the Techstream.

Scheme 40

Scheme 41

1. Connect the Techstream to the DLC3.
2. Turn the ignition switch to ON and turn the Techstream on.
3. Clear DTCs (even if no DTCs are stored, perform the clear DTC operation).
4. Turn the ignition switch off and wait for at least 30 seconds.
5. Turn the ignition switch to ON and turn the Techstream on [A].
6. Depress and release the brake pedal [B].
7. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes [C].
8. Read the DTCs. HINT: If a DTC is output, the system is malfunctioning. If a DTC is not output, perform the following procedure.
9. Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
10. Input the DTC: P0504.
11. Check the DTC judgment result. Tester Display Description NORMAL DTC judgment completed System normal ABNORMAL DTC judgment completed System abnormal INCOMPLETE DTC judgment not completed Perform driving pattern after confirming DTC enabling conditions UNKNOWN Unable to perform DTC judgment Number of DTCs which do not fulfill DTC preconditions has reached ECU memory limit HINT: If the judgment result shows ABNORMAL, the system has a malfunction.
12. If the test result is INCOMPLETE or UNKNOWN and no DTC is output, perform a universal trip and check for permanent DTCs. Refer to «DTC CHECK / CLEAR»(ref-388734-S06424090862011031100000) . HINT: If a permanent DTC is output, the system is malfunctioning. If no permanent DTC is output, the system is normal.

The idling speed is controlled by the ETCS (Electronic Throttle Control System). The ETCS is comprised of: 1) the one valve type throttle body; 2) the throttle actuator, which operates the throttle valve; 3) the Throttle Position (TP) sensor, which detects the opening angle of the throttle valve; 4) the Accelerator Pedal Position (APP) sensor, which detects the accelerator pedal position; and 5) the ECM, which controls the ETCS. Based on the target idling 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 the following conditions are met

1. The learned idling air flow volume remains at the maximum or minimum volume for 5 seconds during a drive cycle.
2. After driving at a vehicle speed of 10 km/h (6.25 mph) or more, the actual engine idling speed varies from the target idling speed by more than -100 rpm or 150 rpm or more when the A/C and NSW are off, or more than -100 rpm or 200 rpm or more when the A/C or NSW are on, 5 times or more during a driving cycle, the ECM illuminates the MIL and sets the DTC.

Scheme 42

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 will 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 engine idling. 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 ETCS (Electronic Throttle Control System) controls the idle speed. The ETCS 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 inspections or repairs, the ISC (Idle Speed Control) learning values are cleared. This DTC cannot be set with the ISC learning values cleared.

HINT

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

Scheme 43

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 will set 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 lower than 50°C (122°F), the ECM checks the ignition timing at 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 set when the malfunction is detected in consecutive driving cycles (2 tip detection logic).

Note. When the negative battery terminal is disconnected during inspections or repairs, the ISC (Idle Speed Control) learning values are cleared. This DTC cannot be set with the ISC learning values cleared.

HINT

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

Scheme 44

The battery supplies electricity to the ECM even when the ignition switch is in the OFF position. 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. When the engine is next 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 is partly erased.

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 the 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 (HO2) sensor transistors built into the ECM. This self-check ensures that the ECM is functioning properly. If outputs from the processors deviate from the standards, the ECM will illuminate the MIL and set the DTC immediately.

Note. An exhaust gas leak generates noise in the HO2 sensor output. The ECM may interpret this as an HO2 sensor transistor malfunction and set P0607.

The main CPU and sub CPU of the ECM perform data communication between each other. The main CPU monitors the communications and WDC pulses from the sub CPU. When the signal malfunctions below are detected, the DTC is output.

The ECM monitors the input signals of the Accelerator Pedal Position (APP) sensor No. 1. When the input signals and control signals are deviated, the DTC is output.

The ECM monitors the input signals of the Throttle Position (TP) sensor No. 1 and stop light switch. As the ECM monitors the input signals of the TP sensor No. 1 and the STP signals of the stop light switch, if the input signals and control signals are deviated, the DTC is output.

The cranking holding control system keeps energizing the starter relay from when the ECM detects the starter signal (STSW signal) from the ignition switch or the main body ECU until the ECM performs a judgement of "Engine started". Furthermore, the ECM outputs an accessory cut signal (ACCR signal) to the ACC cut relay during cranking to prevent flickering of the combination meter, clock, audio system, and so on.

When the ECM detects the STSW signal, the ECM outputs the starter relay drive signal (STAR signal) to the starter relay through the clutch start switch or the park/neutral position switch, and then, the engine is cranked. When the ECM receives a stable engine speed signal (NE signal), more specifically, when the NE signal reaches a predetermined value, the ECM stops outputting the STAR signal.

Also, the ECM monitors the starter relay operating conditions based on the STA terminal voltage status.

Scheme 45

While the engine is being cranked, the 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 20 km/h (12.4 mph) for over 20 seconds.

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

The ECM monitors its internal operation. If the internal operation is malfunctioning, 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 to OFF. If the output voltage is higher than 7 volts when the ignition switch is turned to OFF, the ECM will illuminate the MIL and set the DTC when 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 in lock-up condition.

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 3 km/h [1.86 mph]) and go (30 km/h [1.865 mph] 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. *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.

Scheme 46

Scheme 47

Scheme 48

1. Reference waveforms showing a normal cold engine start
2. Reference waveforms showing a normal warm engine start
3. Reference waveforms showing an engine stop after normal idling
4. Reference values when there is an air leak in the intake system during rough idling FREEZE FRAME DATA P1605 ROUGH IDLING Freeze Frame Data P1605: Rough Idling Parameter -3 -2 -1 0 1 Unit Engine Speed 606 610 572 346 114 rpm Calculate Load 35.6 35.6 36.0 40.7 87.0 % Vehicle Load 19.6 19.2 20.3 60.7 120.3 % MAF 1.56 1.56 1.56 2.76 1.81 gm/sec Atmosphere Pressure -0 -0 -0 -0 -0 psi(gauge) Coolant Temp 186 186 186 186 186 F Intake Air 105 105 105 105 105 F Ambient Temperature 78 78 78 78 78 F Battery Voltage 13.9 13.8 13.8 13.4 13.3 V Throttle Sensor Volt % 14.9 14.9 14.9 16.0 15.2 % Throttle Sensor #2 Volt % 46.6 46.6 46.6 48.2 47.4 % Throttle Sensor Position 0.0 0.0 0.0 0.0 0.0 % Throttle Motor DUTY 14.9 14.9 14.9 16.4 15.2 % Injector (Port) 2430 2430 2300 2560 7420 μs Injection Volume (Cylinder 1) 0.070 0.070 0.070 0.070 0.070 ml Fuel Pump/Speed Status ON ON ON ON ON EVAP (Purge) VSV 0.0 0.0 0.0 0.0 0.0 % Evap Purge Flow 0.0 0.0 0.0 0.0 0.0 % Purge Density Learn Value 0.000 0.000 0.000 0.000 0.000 EVAP purge VSV OFF OFF OFF OFF OFF Target Air-Fuel Ratio 0.999 0.999 0.999 0.999 0.819 AF Lambda B1 S1 1.002 1.002 1.001 1.001 1.002 AFS Voltage B1 S1 3.31 3.31 3.30 3.30 3.31 V O2S B1 S2 0.07 0.07 0.07 0.07 0.07 V Short FT #1 0.7 0.7 0.7 0.7 0.7 % Long FT #1 -1.6 -1.6 -1.6 -1.6 -1.6 % Total FT #1 -0.004 -0.004 -0.004 -0.004 -0.004 Fuel System Status #1 CL CL CL CL OL IGN Advance 5.5 4.5 6.5 4.0 4.0 deg Knock Feedback Value -3.0 -3.0 -3.0 -3.0 -3.0 CA Knock Correct Learn Value 14.0 14.0 14.0 14.0 14.0 CA EGR Step Position 9 9 15 17 20 step VVT Control Status #1 OFF OFF OFF OFF OFF Starter Signal Close Close Close Close Close

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