Engine Control System (2GR-FE) (Diagnostic Codes (P0451-P2A00) & Circuit Tests)): Overview Toyota RAV4 IV

DESCRIPTION

Refer to EVAP (Evaporative Emission) System.Refer to DESCRIPTION.

Scheme 562

1. DTC P0451: Canister pressure sensor signal has noise or is 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 signal 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 is low If the canister pressure sensor output [pressure] is below 42.1 kPa-a (315.9 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 is high If the canister pressure sensor output [pressure] is 123.8 kPa-a (928.4 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).

Refer to EVAP (Evaporative Emission) System.Refer to DESCRIPTION.

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 563

Scheme 564

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 565

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.

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 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 stores 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, both the Data List items Stop Light Switch and ST1 are ON when the brake pedal is depressed because the ST1 indication characteristic is opposite to the Stop Light Switch indication.

Scheme 566

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) [A].
4. Depress and release the brake pedal [B].
5. Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
6. Input the DTC: P0504.
7. Check the DTC judgment result[C]. 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 N/A Unable to perform DTC judgment Number of DTCs which do not fulfill DTC preconditions has reached ECU's memory limit HINT: If the judgment result shows ABNORMAL, the system has a malfunction.
8. If the test result is N/A, enter the following menus: Powertrain / Engine and ECT / Trouble Codes / Pending.
9. Read Pending DTCs. HINT: If a pending DTC is output, the system is malfunctioning.
10. If the test result is INCOMPLETE or N/A and no pending DTC is output, perform a universal trip and check for permanent DTCs.Refer to «DTC CHECK / CLEAR»(ref-493460-S06003279822012081000000). HINT: If a permanent DTC is output, the system is malfunctioning. If no permanent DTC is output, the system is normal.

Scheme 567

The idling speed is controlled by the ETCS (Electronic Throttle Control System). The ETCS is comprised of: 1) a 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 airflow volume to conduct Idle Speed Control (ISC). The ECM determines that the ISC system is malfunctioning if the following conditions are 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 10 km/h (6.25 mph) or more, the difference between the target and actual engine idling speeds 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 568

The Electronic Throttle Control System (ETCS) controls the engine idling speed. The ETCS operates the throttle actuator to open and close the throttle valve, and adjusts the intake air amount to achieve the target idling speed.

In addition, the ECM retards the ignition timing and the ETCS increases the intake air amount to quickly increase the catalyst temperature at cold start to reduce emissions.

Scheme 569

The ECM monitors the intake air amount during idling, and the ignition timing.

When the Engine Coolant Temperature (ECT) is between -10°C and 50°C (14°F and 122°F), the ECM calculates the idling intake air amount for 10 seconds, beginning 3 seconds after the engine starts.

When the accumulated amount is below the threshold, the ECM interprets this as a malfunction in the Idle Speed Control (ISC) system at cold start.

The ECM also monitors the ignition timing at cold start, and judges it to be incorrect when it is advanced to the same value as a warm engine for 5 seconds or more of the 10 second monitoring period.

Example

P050A is detected when all conditions below are met (2 trip detection logic).

1. The ECT is between -10°C and 50°C (14°F and 122°F) when the engine starts.
2. The engine idles for 13 seconds after engine start.
3. The accumulated intake air amount is below the threshold.

The ECM sets the DTC and illuminates the MIL 13 seconds after the engine is next started.

Note. When the negative battery terminal is disconnected during inspection or repairs, the ISC learned values are cleared. The ISC learning must be performed by warming up the engine and idling for 5 minutes with the ECT at 75°C (167°F) or more because DTCs cannot be detected with the ISC learned values cleared.

This monitor will run when the engine is started with the engine coolant temperature at -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 ignition timing at cold start. When the engine is started with the engine coolant temperature 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 trip detection logic).

The ETCS (Electrical 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 cable is disconnected from the negative (-) battery terminal 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 570

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. 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 are partly erased.

The ECM continuously monitors its own internal memory status, internal circuits, and output signals transmitted to the throttle actuator. This self-check ensures 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 standard, 2) the signals sent to the throttle actuator deviate from the standard, 3) a malfunction is found in the throttle actuator supply voltage, or 4) any other ECM malfunction is found.

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 standard, the ECM will illuminate the MIL and set a DTC immediately.

The ECM continuously monitors its internal processors (CPUs) and heated oxygen sensor (HO2S) transistors. This self-check ensures that the ECM is functioning properly. Malfunctions are diagnosed by internal "mirroring" of the main and sub CPUs to detect processor errors. If outputs from the processors deviate from the standard the ECM will illuminate the MIL and set a DTC immediately.

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, this DTC is output.

This DTC is output when a communication error occurs in the ECM.

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

While the engine is being cranked, the positive battery voltage is applied to terminal STA of the ECM. If the ECM detects the Starter Control (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 will set 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 sets 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 incorrect. The VIN is input with 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 higher when the ignition switch is turned off, the ECM will illuminate the MIL and set this DTC when the ignition switch is turned to ON.

The purpose of this circuit is to prevent the engine from stalling while driving in the lock-up condition when the brakes are suddenly applied.

When the brake pedal is depressed, the stop light 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 GO and STOP driving, the ECM interprets this as a fault in the stop light switch. Then the MIL illuminates and the ECM stores the DTC. The vehicle must GO (30 km/h (18.65 mph) or more) and STOP (less than 3 km/h (1.86 mph)) 5 times for 2 driving cycles in order for the DTC to be output.

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 standard, the ECM will illuminate the MIL and set this DTC immediately.

The throttle actuator is operated by the ECM and opens and closes the throttle valve using gears.

The opening angle of the throttle valve is detected by the Throttle Position (TP) sensor, which is mounted on the throttle body. The TP sensor provides feedback to the ECM. This feedback allows the ECM to appropriately control the throttle actuator and monitor the throttle opening angle as the ECM responds to driver inputs.

HINT

This ETCS (Electronic Throttle Control System) does not use a throttle cable.

The ECM monitors the electrical current through the electronic actuator, and detects malfunctions and open circuits in the throttle actuator based on this value. If the current is outside the standard range, the ECM determines that there is a malfunction in the throttle actuator. In addition, if the throttle valve does not function properly (for example, if it is stuck on), the ECM determines that there is a malfunction. The ECM then illuminates the MIL and sets either of these DTCs.

Example

When the electrical current is less than 0.5 A and the throttle actuator duty ratio exceeds 80%, the ECM interprets this as the current being outside the standard range, and illuminates the MIL and sets DTC P2102.

If the malfunction is not repaired successfully, the DTC is set when the engine is quickly revved to a high rpm several times after the engine is started and has idled for 5 seconds.

The throttle actuator is operated by the ECM, and opens and closes the throttle valve using gears. The opening angle of the throttle valve is detected by the Throttle Position (TP) sensor, which is mounted on the throttle body. The TP sensor provides feedback to the ECM so that it can control the throttle actuator (throttle valve) appropriately in response to driver inputs.

HINT

This ETCS (Electronic Throttle Control System) does not use a throttle cable.

The ECM determines that there is a malfunction in the ETCS when the throttle valve remains at a fixed angle despite a high drive current from the ECM. The ECM illuminates the MIL and sets either of these DTCs.

If the malfunction is not repaired successfully, the DTC is set when the accelerator pedal is fully depressed and released quickly (to fully open and close the throttle valve) after the engine is next started.

The ETCS (Electronic Throttle Control System) has a dedicated power supply circuit. The voltage (+BM) is monitored and when it is low (less than 4 V), the ECM determines that there is a malfunction in the ETCS and cuts off the current to the throttle actuator.

When the voltage becomes unstable, the ETCS itself becomes unstable. For this reason, when the voltage is low, the current to the throttle actuator is cut. If repairs are made and the system returns to normal, the ECM then allows the current to flow to the throttle actuator so that it can be restarted after the ignition switch is turned off.

HINT

This ETCS does not use a throttle cable.

Scheme 571

The ECM monitors the battery supply voltage applied to the throttle actuator.

When the power supply voltage (+BM) drops below 4 V for 0.8 seconds or more, the ECM interprets this as an open in the power supply circuit (+BM). The ECM illuminates the MIL and sets the DTC.

If the malfunction is not repaired successfully, the DTC is set 5 seconds after the engine is next started.

The Electronic Throttle Control System (ETCS) is composed of the throttle actuator, Throttle Position (TP) sensor, Accelerator Pedal Position (APP) sensor and ECM. The ECM operates the throttle actuator to regulate the throttle valve in response to driver inputs. The TP sensor detects the opening angle of the throttle valve, and provides the ECM with feedback so that the throttle valve can be appropriately controlled by the ECM.

The ECM determines the actual opening angle of the throttle valve from the TP sensor signal. The actual opening angle is compared to the target opening angle commanded by the ECM. If the difference between these two values is outside the standard range, the ECM interprets this as a malfunction in the ETCS. The ECM then illuminates the MIL and sets the DTC.

If the malfunction is not repaired successfully, the DTC is set when the accelerator pedal is quickly released (to close the throttle valve) after the engine speed reaches 5, 000 rpm by the accelerator pedal being fully depressed (fully opening the throttle valve).

HINT

This ETCS (Electronic Throttle Control System) does not use a throttle cable.

The APP sensor is mounted on the accelerator pedal bracket and has 2 sensor circuits: VPA (main) and VPA2 (sub). This sensor is a non-contact type and uses Hall-effect elements in order to yield accurate signals even in extreme driving conditions, such as at high speeds as well as very low speeds. The voltage, which is applied to terminals VPA and VPA2 of the ECM, varies between 0.5 V and 4.5 V in proportion to the amount the accelerator pedal is depressed (throttle valve opening angle). A signal from VPA indicates the actual accelerator pedal position (throttle valve opening angle) and is used for engine control. A signal from VPA2 conveys the status of the VPA circuit and is used to check the APP sensor itself.

The ECM monitors the actual accelerator pedal position (throttle valve opening angle) through the signals from VPA and VPA2, and controls the throttle actuator according to these signals.

Scheme 572

HINT

When any of these DTCs are set, check the APP sensor voltage by selecting the following menu items on Techstream: Powertrain / Engine and ECT / Data List / Accel Sensor Out No. 1 and Accel Sensor Out No. 2.

HINT

1. Accelerator pedal positions are expressed as voltages.

1. AP stands for Accelerator Pedal.

When either the output voltage of VPA or VPA2 deviates from the standard range, or the difference between the output voltages of the 2 sensor circuits is less than the threshold, the ECM determines that there is a malfunction in the APP sensor. The ECM then illuminates the MIL and sets a DTC.

Example

When the output voltage of VPA drops below 0.4 V for more than 0.5 seconds when the accelerator pedal is fully depressed, DTC P2122 is set.

If the malfunction is not repaired successfully, the DTC is set 2 seconds after the engine is next started.

Refer to DTC P2120.Refer to DESCRIPTION.

The accelerator pedal position sensor is mounted on the accelerator pedal bracket. The accelerator pedal position sensor has 2 sensor elements and 2 signal outputs: VPA and VPA2. VPA is used to detect the actual accelerator pedal angle (used for engine control) and VPA2 is used to detect malfunctions in VPA. When the difference between the output voltages of VPA and VPA2 deviates from the standard, the ECM determines that the accelerator pedal position sensor is malfunctioning. The ECM turns on the MIL and stores the DTC.

The A/F sensor generates a voltage* that corresponds to the actual air-fuel ratio. This sensor voltage is used to provide the ECM with feedback so that it can control the air-fuel ratio. The ECM determines the deviation from the stoichiometric air-fuel ratio and regulates the fuel injection time. If the A/F sensor malfunctions, the ECM is unable to control the air-fuel ratio accurately.

The A/F sensor is of the planar type and is integrated with a heater, which heats the solid electrolyte (zirconia element). This heater is controlled by the ECM. When the intake air volume is low (the exhaust gas temperature is low), a current flows into the heater to heat the sensor in order to facilitate accurate air-fuel ratio detection. The heat generated by the heater is conducted to the solid electrolyte through the alumina, therefore the sensor activation is accelerated.

In order to obtain a high purification rate of the carbon monoxide (CO), hydrocarbon (HC) and nitrogen oxide (NOx) components in the exhaust gas, a TWC is used. For the most efficient use of the TWC, the air-fuel ratio must be precisely controlled so that it is always close to the stoichiometric level.

*: The value changes inside the ECM. Since the A/F sensor is a current output element, the current is converted into a voltage inside the ECM. Any measurements taken at the A/F sensor or ECM connectors will show a constant voltage.

Scheme 573

HINT

1. DTCs P2195 and P2196 indicate malfunctions related to the bank 1 A/F sensor circuit.
2. DTCs P2197 and P2198 indicate malfunctions related to the bank 2 A/F sensor circuit.
3. Bank 1 refers to the bank that includes cylinder No. 1.
4. Bank 2 refers to the bank that includes cylinder No. 2.
5. When any of these DTCs is set, check the A/F sensor output voltage by selecting the following menu items on the Techstream: Powertrain / Engine and ECT / Data List / A/F Control System / AFS Voltage B1S1 or AFS Voltage B2S1.
6. Short-term fuel trim values can also be read using the Techstream.
7. The ECM regulates the voltages at the A1A+ and A1A-, and A2A+ and A2A- terminals of the ECM to a constant level. Therefore, the A/F sensor output voltage cannot be confirmed without using the Techstream.
8. If the A/F sensor is malfunctioning, the ECM sets the DTC P2195, P2196, P2197 or P2198.

Sensor voltage detection monitor

Under the air-fuel ratio feedback control, if the A/F sensor output voltage indicates a rich or lean air-fuel ratio for a certain period of time, the ECM determines that there is a malfunction in the A/F sensor. The ECM illuminates the MIL and sets a DTC.

Example

If the A/F sensor output voltage is less than 2.8 V (a very rich condition) for 5 seconds, despite the rear HO2 sensor output voltage being less than 0.59 V, the ECM sets DTC P2196 or P2198. Alternatively, if the A/F sensor output voltage is more than 3.8 V (a very lean condition) for 5 seconds, despite the rear HO2 sensor output voltage being 0.21 V or more, DTC P2195 or P2197 is set.

Sensor current detection monitor

A rich air-fuel mixture causes a low A/F sensor current, and a lean air-fuel mixture causes a high A/F sensor current. Therefore, the sensor output becomes low during acceleration, and it becomes high during deceleration with the throttle valve fully closed. The ECM monitors the A/F sensor current during fuel-cut and detects any abnormal current values.

If the A/F sensor output is 3.6 mA or more for more than 3 seconds of cumulative time, the ECM interprets this as a malfunction in the A/F sensor and sets DTC P2195 or P2197 (stuck on high side). If the A/F sensor output is less than 1.4 mA for more than 3 seconds of cumulative time, the ECM sets DTC P2196 or P2198 (stuck on low side).

Scheme 574

Refer to DTC P2195.Refer to DESCRIPTION.

HINT

1. DTCs P2237, P2238, P2239, P2252 and P2253 indicate malfunctions related to the bank 1 A/F sensor circuit.
2. DTCs P2240, P2241, P2242, P2255 and P2256 indicate malfunctions related to the bank 2 A/F sensor circuit.
3. Bank 1 refers to the bank that includes cylinder No. 1.
4. Bank 2 refers to the bank that includes cylinder No. 2.

The Air-Fuel Ratio (A/F) sensor varies its output voltage in proportion to the air-fuel ratio. If the A/F sensor impedance (alternating current resistance) or output voltage deviates greatly from the standard range, the ECM determines that there is an open or short in the A/F sensor circuit.

Refer to EVAP (Evaporative Emission) System.Refer to 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.

P2420: Vent valve stuck open (vent)

In operation C, the vent valve turns ON (closes), and the EVAP system pressure is then measured by the ECM using the canister pressure sensor to conduct an EVAP leak check. If the pressure does not increase when the vent valve is commanded to close, the ECM interprets this as the vent valve being stuck open. The ECM illuminates the MIL and sets the DTC.

Scheme 575

The soak timer operates after the ignition switch is turned off. When a certain amount of time has elapsed after turning the ignition switch off the soak timer activates the ECM to perform malfunction checks which can only be performed after the engine is stopped. The soak timer is built into the ECM.

Scheme 576

1. While the engine is running, the ECM monitors the synchronization of the soak timer and the CPU clock. If these two are not synchronized, the ECM interprets this as a malfunction, illuminates the MIL and stores the DTC.
2. If the soak timer activates the ECM even though only a short amount of time has elapsed since the ignition switch was turned off, or if the soak timer does not activate the ECM even though a considerable amount of time has elapsed since the ignition switch was turned off, the ECM determines that the soak timer is malfunctioning, illuminates the MIL and stores a DTC the next time the ignition switch is turned ON.

Refer to DTC P2195.Refer to DESCRIPTION.

After the engine is warmed up, the ECM performs air-fuel ratio feedback control to maintain the air-fuel ratio at the stoichiometric level. In addition, active A/F control is performed for approximately 10 seconds after the preconditions are met in order to measure the A/F sensor response rate. During active A/F control, the ECM forcibly increases and decreases the injection volume a certain amount, based on the stoichiometric air-fuel ratio learned during normal air-fuel ratio control, and measures the A/F sensor response rate. The ECM receives a signal from the A/F sensor while performing active A/F control and uses it to calculate the A/F sensor response rate deterioration level.

If the A/F sensor response rate deterioration level is less than the threshold, the ECM interprets this as a malfunction and sets the DTC.

Scheme 577

When the ignition switch is turned to ON, the battery voltage is applied to terminal IGSW of the ECM. The output signal from the MREL terminal of the ECM causes a current to flow to the coil, closing the contacts of the integration relay (EFI MAIN relay) and supplying power to both terminal +B and +B2 of the ECM.

Scheme 578

Scheme 579

Scheme 580

Scheme 581

Scheme 582

Scheme 583

Scheme 584

Scheme 585

Scheme 586

Scheme 587

Scheme 588

1. INSPECT INTEGRATION RELAY (INTEGRATION RELAY - BODY GROUND) Remove the integration relay from the engine room No. 1 relay block. Measure the voltage between the terminal of the integration relay and body ground. Standard voltage Tester Connection Specified Condition Engine room relay block (1C-1) - Body ground 11 to 14 V Reinstall the integration relay. NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR (INTEGRATION RELAY - BATTERY) OK: Go to next step
2. INSPECT INTEGRATION RELAY (EFI MAIN RELAY) Inspect the integration relay.Refer to «ON-VEHICLE INSPECTION»(ref-493466-S42585886872012081000000). NG --> REPLACE INTEGRATION RELAY OK: Go to next step
3. CHECK HARNESS AND CONNECTOR (+B, +B2 AND MREL CIRCUIT) Check the harness and connectors between the integration relay and ECM. Remove the integration relay from the engine room No. 1 relay block. Disconnect the A9 ECM connector. Measure the resistance between the wire harness side connectors. Standard resistance (Check for open) Tester Connection Specified Condition A9-34 (MREL) - Engine room relay block (1A-2) Below 1 ohms A9-3 (+B) - Engine room relay block (1A-4) A9-2 (+B2) - Engine room relay block (1A-4) Standard resistance (Check for short) Tester Connection Specified Condition A9-34 (MREL) or Engine room relay block (1A-2) - Body ground 10 kohms or higher A9-3 (+B) or Engine room relay block (1A-4) - Body ground A9-2 (+B2) or Engine room relay block (1A-4) - Body ground Check the harness and connectors between the integration relay and body ground. Measure the resistance between the wire harness side connector and body ground. Standard resistance (Check for open) Tester Connection Specified Condition Engine room relay block (1A-3) - Body ground Below 1 ohms Reinstall the integration relay. Reconnect the ECM connector. NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
4. CHECK HARNESS AND CONNECTOR (ECM - BODY GROUND) Disconnect the B30 ECM connector. Measure the resistance. Standard resistance (Check for open) Tester Connection Specified Condition B30-81 (E1) - Body ground Below 1 ohms Reconnect the ECM connector. NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
5. INSPECT ECM (IGSW VOLTAGE) Disconnect the B30 and A9 ECM connectors. Turn the ignition switch to ON. Measure the voltage between the terminals of the B30 and A9 ECM connectors. Standard voltage Tester Connection Specified Condition A9-28 (IGSW) - B30-81 (E1) 11 to 14 V Reconnect the ECM connectors. OK --> REPLACE ECM NG: Go to next step
6. INSPECT FUSE (IGN AND IG2 FUSE) Remove the IGN fuse from the main body ECU (instrument panel junction block). Remove the IG2 fuse from the engine room No. 1 relay block. Measure the IGN and IG2 fuse resistance. Standard resistance Below 1 ohms Reinstall the IGN fuse. Reinstall the IG2 fuse. NG --> CHECK FOR SHORT IN ALL HARNESSES AND COMPONENTS CONNECTED TO FUSE, AND REPLACE FUSE OK: Go to next step
7. INSPECT IG2 RELAY Remove the IG2 relay from the engine room No. 1 relay block. Measure the resistance. Standard resistance Tester Connection Specified Condition 3 - 5 10 kohms or higher 3 - 5 Below 1 ohms (Battery voltage applied to terminals 1 and 2) Reinstall the relay. NG --> REPLACE IG2 RELAY OK: Go to next step
8. CHECK HARNESS AND CONNECTOR (ECM - ENGINE ROOM NO. 1 RELAY BLOCK) Remove the IG2 relay from the engine room No. 1 relay block. Disconnect the A9 ECM connector. Measure the resistance between the wire harness side connectors. Standard resistance (Check for open) Tester Connection Specified Condition Relay block IG2 relay terminal (5) - A9-28 (IGSW) Below 1 ohms Standard resistance (Check for short) Tester Connection Specified Condition Relay block IG2 relay terminal (5) or A9-28 (IGSW) - Body ground 10 kohms or higher Reinstall the IG2 relay. Reconnect the ECM connector. Result Result Proceed to Out of normal range A Within normal range (with Smart Key System) B Within normal range (without Smart Key System) C B --> See step 9 C --> See step 10 A --> REPAIR OR REPLACE HARNESS OR CONNECTOR
9. CHECK HARNESS AND CONNECTOR (ENGINE ROOM NO. 1 RELAY BLOCK - MAIN BODY ECU) Remove the IG2 relay from the engine room No. 1 relay block. Disconnect the E16 instrument panel junction block (main body ECU) connector. Measure the resistance between the wire harness side connectors. Standard resistance (Check for open) Tester Connection Specified Condition Relay block IG2 relay terminal (1) - E16-5 (IG2D) Below 1 ohms Relay block IG2 relay terminal (2) - Body ground Below 1 ohms Standard resistance (Check for short) Tester Connection Specified Condition E16-5 (IG2D) - Body ground 10 kohms or higher Reinstall the IG2 relay. Reconnect the instrument panel junction block (main body ECU) connector. OK --> See step 12 NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR
10. CHECK HARNESS AND CONNECTOR (ENGINE ROOM NO. 1 RELAY BLOCK - IGNITION SWITCH) Remove the IG2 relay from the engine room No. 1 relay block. Disconnect the E3 ignition switch connector. Measure the resistance between the wire harness side connectors. Standard resistance (Check for open) Tester Connection Specified Condition Relay block IG2 relay terminal (1) - E3-6 (IG2) Below 1 ohms Relay block IG2 relay terminal (2) - Body ground Below 1 ohms Standard resistance (Check for short) Tester Connection Specified Condition E3-6 (IG2) - Body ground 10 kohms or higher Reinstall the IG2 relay. Reconnect the ignition switch connector. NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
11. INSPECT IGNITION SWITCH ASSEMBLY Inspect the ignition switch.Refer to «INSPECTION»(ref-493465-S39120384072012081000000). NG --> See step 13 OK --> REPAIR OR REPLACE HARNESS OR CONNECTOR (IGNITION SWITCH - BATTERY)
12. CHECK SMART KEY SYSTEM. Refer to «HOW TO PROCEED WITH TROUBLESHOOTING»(ref-493473-S06846861712012081000000)
13. REPLACE IGNITION SWITCH ASSEMBLY. Refer to «REMOVAL»(ref-493465-S06761995212012081000000)

The ECM constantly generates a 5 V power source voltage from the battery voltage supplied to the +B (BATT) terminal to operate the microprocessor. The ECM also provides this power source voltage to the sensors through the VC output circuit.

Scheme 589

When the VC circuit is short-circuited, the microprocessor in the ECM and sensors that are supplied with power through the VC circuit are inactivated because the power is not supplied from the VC circuit. Under this condition, the system does not start up and the MIL does not illuminate even if the system malfunctions.

HINT

Under normal conditions, the MIL is illuminated for several seconds when the ignition switch is first turned to ON, and then goes off when the engine starts.

Scheme 590

Scheme 591

Scheme 592

1. CHECK MIL Check that the Malfunction Indicator Lamp (MIL) lights up when turning the ignition switch to ON. OK MIL lights up. OK --> SYSTEM OK NG: Go to next step
2. CHECK COMMUNICATION BETWEEN TECHSTREAM AND ECM Connect the Techstream to the DLC3. Turn the ignition switch to ON and turn the Techstream ON. Check the communication between the Techstream and ECM. Result Result Proceed to Communication is possible A Communication is not possible B A --> See step 11 B: Go to next step
3. CHECK MIL (THROTTLE POSITION SENSOR) Disconnect the B3 throttle body connector. Turn the ignition switch to ON. Check the MIL. Result Result Proceed to MIL illuminates A MIL does not illuminate B Reconnect the throttle body connector. A --> See step 12 B: Go to next step
4. CHECK MIL (ACCELERATOR PEDAL POSITION SENSOR) Disconnect the A4 accelerator pedal position sensor connector. Turn the ignition switch to ON. Check the MIL. Result Result Proceed to MIL illuminates A MIL does not illuminate B Reconnect the accelerator pedal position sensor connector. A --> See step 13 B: Go to next step
5. CHECK MIL (VVT SENSOR FOR BANK 1 INTAKE SIDE) Disconnect the B59 VVT sensor connector. Turn the ignition switch to ON. Check the MIL. Result Result Proceed to MIL illuminates A MIL does not illuminate B Reconnect the VVT sensor connector. A --> See step 14 B: Go to next step
6. CHECK MIL (VVT SENSOR FOR BANK 1 EXHAUST SIDE) Disconnect the B54 VVT sensor connector. Turn the ignition switch to ON. Check the MIL. Result Result Proceed to MIL illuminates A MIL does not illuminate B Reconnect the VVT sensor connector. A --> See step 15 B: Go to next step
7. CHECK MIL (VVT SENSOR FOR BANK 2 EXHAUST SIDE) Disconnect the B40 VVT sensor connector. Turn the ignition switch to ON. Check the MIL. Result Result Proceed to MIL illuminates A MIL does not illuminate B Reconnect the VVT sensor connector. A --> See step 16 B: Go to next step
8. CHECK MIL (VVT SENSOR FOR BANK 2 INTAKE SIDE) Disconnect the B45 VVT sensor connector. Turn the ignition switch to ON. Check the MIL. Result Result Proceed to MIL illuminates A MIL does not illuminate B Reconnect the VVT sensor connector. A --> See step 17 B: Go to next step
9. CHECK MIL (CANISTER PUMP MODULE) Disconnect the S3 canister pump module connector. Turn the ignition switch to ON. Check the MIL. Result Result Proceed to MIL illuminates A MIL does not illuminate B Reconnect the canister pump module connector. A --> See step 18 B: Go to next step
10. CHECK WIRE HARNESS Disconnect the B3 throttle body connector. Disconnect the A4 accelerator pedal position sensor connector. Disconnect the S3 canister pump module connector. Disconnect the B59 VVT sensor connector. Disconnect the B45 VVT sensor connector. Disconnect the B54 VVT sensor connector. Disconnect the B40 VVT sensor connector. Disconnect the A9 and B30 ECM connectors. Measure the resistance. Standard resistance Tester Connection Specified Condition B30-80 (VCTA) - Body ground 10 kohms or higher A9-57 (VCPA) - Body ground 10 kohms or higher A9-59 (VCP2) - Body ground 10 kohms or higher B30-67 (VCV1) - Body ground 10 kohms or higher B30-66 (VCV2) - Body ground 10 kohms or higher Reconnect the throttle body connector. Reconnect the accelerator pedal position sensor connector. Reconnect the canister pump module connector. Reconnect the VVT sensor connectors. Reconnect the ECM connectors. NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK --> See step 19
11. GO TO MIL CIRCUIT. Refer to «MIL Circuit»(ref-493463-S41260471082012081000000)
12. REPLACE THROTTLE BODY ASSEMBLY. Refer to «REMOVAL»(ref-493466-S05114120172012081000000)
13. REPLACE ACCELERATOR PEDAL ASSEMBLY. Refer to «REMOVAL»(ref-493466-S03195754632012081000000)
14. REPLACE VVT SENSOR (FOR BANK 1 INTAKE SIDE). Refer to «REMOVAL»(ref-493466-S37404021992012081000000)
15. REPLACE VVT SENSOR (FOR BANK 1 EXHAUST SIDE). Refer to «REMOVAL»(ref-493466-S37404021992012081000000)
16. REPLACE VVT SENSOR (FOR BANK 2 EXHAUST SIDE). Refer to «REMOVAL»(ref-493466-S37404021992012081000000)
17. REPLACE VVT SENSOR (FOR BANK 2 INTAKE SIDE). Refer to «REMOVAL»(ref-493466-S37404021992012081000000)
18. REPLACE CHARCOAL CANISTER ASSEMBLY. Refer to «REMOVAL»(/toyota/rav4/iv-2012-2015/remont/auxiliary-emission-control-systems/#emission-control-system-2gr-fe-service-information)
19. REPLACE ECM. Refer to «REMOVAL»(ref-493466-S41904497902012081000000)

The F/PMP relay switches the fuel pump speed according to the engine conditions. The fuel pump operates when the ECM receives the starter-operating signal (STA) and crankshaft-rotating signal (NE). The F/PMP relay is turned ON while the engine is idling or operating at low load. This causes current to flow through the fuel pump resistor to the fuel pump. The fuel pump then operates at low speed. The F/PMP relay is turned OFF while the engine is cranking or operating at high load. The fuel pump then operates at normal speed.

Scheme 593

Scheme 594

Scheme 595

Scheme 596

Scheme 597

Scheme 598

Scheme 599

Scheme 600

1. PERFORM ACTIVE TEST USING TECHSTREAM (FUEL PUMP/SPD) Connect the Techstream to the DLC3. Turn the ignition switch to ON and turn the Techstream ON. Select the following menu items: Powertrain / Engine and ECT / Active Test / Control the Fuel Pump / Speed. Check whether the fuel pump operating sound occurs when performing the Active Test on the Techstream. OK Fuel pump operating sound occurs. OK --> See step 12 NG: Go to next step
2. INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY (C/OPN RELAY INPUT VOLTAGE) Measure the voltage between the terminal of the instrument panel junction block and the body ground when the ignition switch is turned to ON and off. Standard voltage Tester Connection Ignition Switch Condition Specified Condition IB-11 - Body ground Off Below 1 V IF-4 - Body ground IB-11 - Body ground ON 11 to 14 V IF-4 - Body ground OK --> See step 4 NG: Go to next step
3. CHECK WIRE HARNESS (INSTRUMENT PANEL JUNCTION BLOCK - INTEGRATION RELAY AND IG2 RELAY) Remove the integration relay and IG2 relay from the engine room No. 1 relay block. Disconnect the instrument panel junction block connectors. Measure the resistance. Standard resistance Tester Connection Specified Condition IG2 relay 5 - IF-4 Below 1 ohms 1A-4 - IB-11 Below 1 ohms IF-4 - Body ground 10 kohms or higher IB-11 - Body ground 10 kohms or higher Reinstall the integration relay and IG2 relay. Reconnect the instrument panel junction block connectors. NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK --> See step 14
4. INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY (C/OPN RELAY) Remove the instrument panel junction block. Measure the C/OPN relay resistance. Standard resistance Tester Connection Specified Condition IB-11 - IA-8 10 kohms or higher Below 1 ohms (Battery voltage is applied to terminals IF-4 and IE-5) HINT: The relay coil circuit between IF-4 and IE-5 is through the IGN fuse. Reinstall the instrument panel junction block. NG --> REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY OK: Go to next step
5. CHECK WIRE HARNESS (INSTRUMENT PANEL JUNCTION BLOCK - ECM) Disconnect the A9 ECM connector. Disconnect the IE connector from the instrument panel junction block. Measure the resistance. Standard resistance Tester Connection Specified Condition IE-5 - A9-52 (FC) Below 1 ohms IE-5 or A9-52 (FC) - Body ground 10 kohms or higher Reconnect the instrument panel junction block and ECM connectors. NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
6. PERFORM ACTIVE TEST USING TECHSTREAM (FUEL PUMP/SPD) Connect the Techstream to the DLC3. Turn the ignition switch to ON and turn the Techstream ON. Select the following menu items: Powertrain / Engine and ECT / Active Test / Control the Fuel Pump / Speed. Check the operating noise of the relay while operating it using the Techstream. OK Operating noise can be heard from the relay. OK --> See step 9 NG: Go to next step
7. INSPECT F/PMP RELAY. Refer to «PROCEDURE - Step 2»(ref-493462-S07850968282012081000000) NG --> See step 15 OK: Go to next step
8. CHECK WIRE HARNESS (F/PMP RELAY - ECM AND INSTRUMENT PANEL JUNCTION BLOCK) Remove the F/PMP relay from the engine room No. 1 relay block. Disconnect the A9 ECM connector. Disconnect the IA instrument panel junction block connector. Measure the resistance. Standard resistance Tester Connection Specified Condition F/PMP relay terminal 1 - A9-48 (FPR) Below 1 ohms F/PMP relay terminal 2 - IA-8 Below 1 ohms F/PMP relay terminal 3 - IA-8 Below 1 ohms F/PMP relay terminal 1 or A9-48 (FPR) - Body ground 10 kohms or higher F/PMP relay terminal 2 or IA-8 - Body ground 10 kohms or higher F/PMP relay terminal 3 or IA-8 - Body ground 10 kohms or higher Reconnect the ECM connector. Reconnect the instrument panel junction block connector. Reinstall the F/PMP relay. NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
9. CHECK WIRE HARNESS (F/PMP - FUEL PUMP AND PUMP RESISTOR) Remove the F/PMP relay from the engine room No. 1 relay block. Disconnect the S1 fuel pump connector. Disconnect the A20 fuel pump resistor connector. Measure the resistance. Standard resistance Tester Connection Specified Condition F/PMP relay terminal 4 - S1-4 Below 1 ohms F/PMP relay terminal 5 - A20-1 Below 1 ohms A20-2 - S1-4 Below 1 ohms S1-5 - Body ground Below 1 ohms F/PMP relay terminal 4 or S1-4 - Body ground 10 kohms or higher F/PMP relay terminal 5 or A20-1 - Body ground 10 kohms or higher A20-2 or S1-4 - Body ground 10 kohms or higher Reconnect the fuel pump resistor connector. Reconnect the fuel pump connector. Reinstall the F/PMP relay. NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK: Go to next step
10. INSPECT FUEL PUMP Inspect the fuel pump resistance. Measure the resistance between the terminals. Standard resistance 0.2 to 3.0 ohms at 20°C (68°F) Inspect the fuel pump operation. Apply battery voltage to the terminals. Check that the pump operates. NOTE: This test must be done quickly (within 10 seconds) to prevent the coil from burning out. Keep the fuel pump as far away from the battery as possible. Always turn the voltage on and off on the battery side, not the fuel pump side. NG --> See step 16 OK: Go to next step
11. INSPECT FUEL PUMP RESISTOR Measure the resistance of the fuel pump resistor. Standard resistance 0.30 to 0.34 ohms at 20°C (68°F) NG --> See step 17 OK --> See step 18
12. READ VALUE USING TECHSTREAM (STARTER SIG) Connect the Techstream to the DLC3. Turn the ignition switch to ON and turn the Techstream ON. Select the following menu items: Powertrain / Engine and ECT / Data List / Starter Signal. Check the result when the ignition switch is turned to ON and START. OK Ignition Switch Position Starter Signal ON OFF START ON NG --> REPAIR OR REPLACE STARTING SYSTEM OK: Go to next step
13. READ VALUE USING TECHSTREAM (ENGINE SPD) Connect the Techstream to the DLC3. Turn the ignition switch to ON and turn the Techstream ON. Select the following menu items: Powertrain / Engine and ECT / Data List / Engine Speed. Read the values displayed on the Techstream while cranking. Standard Values are displayed continuously. NG --> REPAIR OR REPLACE CRANKSHAFT POSITION SENSOR CIRCUIT OK --> See step 19
14. GO TO ECM POWER SOURCE CIRCUIT. Refer to «ECM Power Source Circuit»(ref-493463-S18863697402012081000000)
15. REPLACE F/PMP RELAY. Refer to «REMOVAL»(ref-493467-S22560231592012081000000)
16. REPLACE FUEL PUMP. Refer to «REMOVAL»(ref-493467-S31356503202012081000000)
17. REPLACE FUEL PUMP RESISTOR. Refer to «REMOVAL»(ref-493467-S22560231592012081000000)
18. REPLACE ECM. Refer to «REMOVAL»(ref-493466-S41904497902012081000000)
19. REPLACE ECM. Refer to «REMOVAL»(ref-493466-S41904497902012081000000)

The fuel injectors are located on the intake manifold. They inject fuel into the cylinders based on the signals from the ECM.

Scheme 601

Scheme 602

Scheme 603

1. CHECK FUEL INJECTOR ASSEMBLY (POWER SOURCE) Disconnect the fuel injector assembly connector. Turn the ignition switch ON. Measure the voltage according to the value(s) in the table below. Standard voltage Cylinder Tester Connection Switch Condition Specified Condition No. 1 B53-2 - Body ground Ignition switch ON 11 to 14 V No. 2 B37-2 - Body ground Ignition switch ON 11 to 14 V No. 3 B52-2 - Body ground Ignition switch ON 11 to 14 V No. 4 B36-2 - Body ground Ignition switch ON 11 to 14 V No. 5 B51-2 - Body ground Ignition switch ON 11 to 14 V No. 6 B35-2 - Body ground Ignition switch ON 11 to 14 V Turn the ignition switch off. Reconnect the fuel injector assembly connector. NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR (INTEGRATION RELAY (IG2 RELAY) - FUEL INJECTOR ASSEMBLY) OK: Go to next step
2. INSPECT FUEL INJECTOR ASSEMBLY Inspect the injector assembly.Refer to «INSPECTION - Step 1»(ref-493467-S35831074072012081000000). NG --> See step 4 OK: Go to next step
3. CHECK HARNESS AND CONNECTOR (FUEL INJECTOR ASSEMBLY - ECM) Disconnect the injector connector. Disconnect the B30 ECM connector. Measure the resistance according to the value(s) in the table below. Standard resistance Cylinder Tester Connection Specified Condition No. 1 B53-1 - Body ground 10 kohms or higher B53-1 - B30-86 (#10) Below 1 ohms No. 2 B37-1 - Body ground 10 kohms or higher B37-1 - B30-109 (#20) Below 1 ohms No. 3 B52-1 - Body ground 10 kohms or higher B52-1 - B30-85 (#30) Below 1 ohms No. 4 B36-1 - Body ground 10 kohms or higher B36-1 - B30-108 (#40) Below 1 ohms No. 5 B51-1 - Body ground 10 kohms or higher B51-1 - B30-84 (#50) Below 1 ohms No. 6 B35-1 - Body ground 10 kohms or higher B35-1 - B30-107 (#60) Below 1 ohms Reconnect the injector connector. Reconnect the ECM connector. NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK --> See step 5
4. REPLACE FUEL INJECTOR ASSEMBLY. Refer to «REMOVAL»(ref-493467-S37933332382012081000000)
5. REPLACE ECM. Refer to «REMOVAL»(ref-493466-S41904497902012081000000)

The cranking holding control system keeps energizing the ST relay after the ECM detects the starter signal (STSW signal) from the main body ECU until the ECM performs a judgment of "Engine started". Furthermore, the ECM outputs an accessory cut signal (ACCR signal) to the ACC 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 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 ST relay operating conditions based on the STA terminal voltage status.

Scheme 604

This circuit opens and closes the Intake Air Control Valve (IACV) in response to changes in the engine load in order to increase the intake efficiency (ACIS: Acoustic Control Induction System).

When the engine speed is between 0 and 4, 450 rpm and the throttle valve opening angle is 60° or more, the ECM supplies current to the VSV (ON status) to close the IACV. Under other conditions, the VSV is usually OFF and the IACV is open.

Scheme 605

Scheme 606

Scheme 607

Scheme 608

1. PERFORM ACTIVE TEST USING TECHSTREAM (OPERATE VSV FOR ACIS) Connect the Techstream to the DLC3. Start the engine and turn the Techstream on. Select the following menu items: Powertrain / Engine and ECT / Active Test / Activate the VSV for Intake Control. OK Operating noise can be heard. OK --> See step 5 NG: Go to next step
2. CHECK INTAKE AIR CONTROL VALVE (OPERATION) Disconnect the B58 intake air control valve connector. Apply battery voltage to the terminals of the intake air control valve connector. Check the intake air control valve operation. OK Operating noise can be heard. NG --> REPLACE INTAKE AIR SURGE TANK OK: Go to next step
3. CHECK WIRE HARNESS (INTAKE AIR CONTROL VALVE - ECM, INTEGRATION RELAY) Remove the EFI No. 1 fuse from the engine room No. 1 relay block. Check the EFI No. 1 fuse. Reinstall the EFI No. 1 fuse. Disconnect the B58 intake air control valve connector. Disconnect the B30 ECM connector. Remove the integration relay from the engine room No. 1 relay block. Disconnect the 1A integration relay connector. Measure the resistance of the wire harness side connectors. Standard resistance Tester Connection Specified Condition B58-1 - B30-62 (ACIS) Below 1 ohms B58-2 - 1A-4 Below 1 ohms B58-1 or B30-62 (ACIS) - Body ground 10 kohms or higher B58-2 or 1A-4 - Body ground 10 kohms or higher Reconnect the intake air control valve connector. Reconnect the ECM connector. Reconnect the integration relay connector. Reinstall the integration relay. NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK --> See step 4
4. REPLACE ECM. Refer to «REMOVAL»(ref-493466-S41904497902012081000000)
5. PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to «PROBLEM SYMPTOMS TABLE»(ref-493460-S25464997372012081000000)

The air cleaner is equipped with 2 inlets, one of which is opened or closed by the Air Intake Control Valve (AICV). This system reduces intake noise and increases engine power from low to high engine speeds.

When the engine is operating in the low-to-mid speed range, this control operates the AICV to close one of the air cleaner inlets. When the engine speed is more than 3, 600 rpm and the opening angle of the throttle valve is more than 60°, the ECM activates the VSV and opens the AICV.

Scheme 609

Scheme 610

Scheme 611

Scheme 612

1. PERFORM ACTIVE TEST USING TECHSTREAM (ACTIVATE VSV FOR AICS) Connect the Techstream to the DLC3. Turn the ignition switch to ON and turn the Techstream ON. Select the following menu items: Powertrain / Engine and ECT / Active Test / Activate the VSV for AICS. Check the operation of the VSV when the VSV is operated by the Techstream. OK Tester Operation Specified Condition VSV is ON Air from port E flows out through port F VSV is OFF Air from port E flows out through the air filter OK --> See step 4 NG: Go to next step
2. INSPECT AICV VSV Inspect the AICV VSV.Refer to «ON-VEHICLE INSPECTION - Step 4»(/toyota/rav4/iv-2012-2015/remont/mechanical/#engine-intake-system-2gr-fe-inspection) . NG --> REPLACE AICV VSV OK: Go to next step
3. CHECK WIRE HARNESS (AICV VSV - ECM AND INTEGRATION RELAY) Remove the EFI No. 1 fuse from the engine room No. 1 relay block. Check the EFI No. 1 fuse. Reinstall the EFI No. 1 fuse. Disconnect the B31 AICV VSV connector. Disconnect the B30 ECM connector. Remove the integration relay from the engine room No. 1 relay block. Disconnect the 1A integration relay connector. Measure the resistance of the wire harness side connectors. Standard resistance Tester Connection Specified Condition B31-2 - B30-61 (AICV) Below 1 ohms B31-1 - 1A-4 Below 1 ohms B31-2 or B30-61 (AICV) - Body ground 10 kohms or higher B31-1 or 1A-4 - Body ground 10 kohms or higher Reconnect the integration relay connector. Reinstall the integration relay. Reconnect the ECM connector. Reconnect the AICV VSV connector. NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK --> See step 5
4. CHECK VACUUM PIPING (HOSE, INTAKE MANIFOLD AND VACUUM TANK) NG --> REPAIR OR REPLACE VACUUM LEAKAGE POINT OK --> REPAIR COMPLETED
5. REPLACE ECM. Refer to «REMOVAL»(ref-493466-S41904497902012081000000)

When the vehicle is being driven with the accelerator pedal depressed, depressing the brake pedal without releasing the accelerator pedal will activate the brake override system to restrict driving torque. The conditions for activating the brake override system as well as the items that are controlled are explained below.

Scheme 613

Activation Conditions

1. Vehicle is running at or above the specified speed.
2. The accelerator pedal is depressed beyond a specified level, and then the brake pedal is depressed.

Note. The vehicle may not enter the brake override system control due to the relation of the accelerator pedal angle and the vehicle's speed.

Items Controlled

1. Driving torque is restricted.

HINT

During brake override system control, the value for the accelerator pedal angle is forcibly reduced to a specified value. For this reason, the Data List value for Accelerator Position will be replaced with a specified value regardless of the actual accelerator pedal angle (Accel Sens. No. 1 Volt %, Accel Sens. No. 2 Volt %)

Deactivation Conditions

1. When the Stop Light Switch turns OFF or the actual accelerator pedal angle increases or decreases beyond the specified range.

The MIL (Malfunction Indicator Lamp) is used to indicate the detection of vehicle malfunctions by the ECM. When the ignition switch is turned to ON, power is supplied to the MIL circuit and the ECM provides the circuit ground which illuminates the MIL.

The MIL operation can be checked visually; when the ignition switch is first turned to ON, the MIL should be illuminated and should then turn off. If the MIL remains illuminated or is not illuminated, conduct the following troubleshooting procedure using the Techstream.

Scheme 614

Scheme 615

Scheme 616

1. CHECK THAT MIL IS ILLUMINATED Perform troubleshooting in accordance with the table below. RESULT Condition Proceed to MIL remains ON A MIL does not illuminate B B --> See step 5 A: Go to next step
2. CHECK WHETHER MIL TURNS OFF Connect the Techstream to the DLC3. Turn the ignition switch to ON and turn the Techstream ON. Select the following menu items: Powertrain / Engine and ECT / Trouble Code. Check if any DTCs have been stored. Note down any DTCs. Clear DTCs.Refer to «DTC CHECK / CLEAR»(ref-493460-S06003279822012081000000). Check if the MIL goes off. OK MIL should go off. OK --> REPAIR CIRCUITS INDICATED BY OUTPUT DTCS NG: Go to next step
3. CHECK WIRE HARNESS (CHECK FOR SHORT IN WIRE HARNESS) Disconnect the A9 ECM connector. Turn the ignition switch to ON. Check that the MIL is not illuminated. OK MIL is not illuminated. Reconnect the ECM connector. OK --> See step 8 NG: Go to next step
4. CHECK WIRE HARNESS (COMBINATION METER - ECM) Disconnect the A9 ECM connector. Disconnect the E19 combination meter connector. Measure the resistance. Standard resistance Tester Connection Specified Condition A9-24 (W) or E19-8 (EFI) - Body ground 10 kohms or higher Reconnect the ECM connector. Reconnect the combination meter connector. OK --> REPAIR OR REPLACE COMBINATION METER ASSEMBLY NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR
5. CHECK THAT MIL IS ILLUMINATED Check if the MIL is illuminated when the ignition switch is turned to ON. OK MIL is illuminated. OK --> SYSTEM OK NG: Go to next step
6. CHECK THAT ENGINE STARTS Turn the ignition switch to ON. Check that the engine starts. Result Result Proceed to Engine starts A Engine does not start* B HINT: *: The Techstream cannot communicate with the ECM. B --> See step 9 A: Go to next step
7. INSPECT COMBINATION METER ASSEMBLY (MIL CIRCUIT) Check the MIL circuit.Refer to «PROBLEM SYMPTOMS TABLE»(ref-493475-S12192452932012081000000). NG --> REPAIR OR REPLACE COMBINATION METER ASSEMBLY OK --> CHECK AND REPLACE HARNESS AND CONNECTOR (COMBINATION METER - ECM)
8. REPLACE ECM. Refer to «REMOVAL»(ref-493466-S41904497902012081000000)
9. GO TO VC OUTPUT CIRCUIT. Refer to «VC Output Circuit»(ref-493463-S32381055702012081000000)

See also:
• REMOVAL
• ON-VEHICLE INSPECTION - Step 2
• ON-VEHICLE INSPECTION - Step 4