Pre-Collision System (Diagnostic Codes & Circuit Tests): Overview Lexus GS IV

DESCRIPTION

The seat belt control ECU receives collision information from the driving support ECU and skid control ECU via CAN communication, and tightens the seat belt by operating the motor inside the front seat outer belt assembly.

When DTC B2000 is detected, DTCs B2016, B2026, B2027, and B2035 will not be detected.

When DTC B2005 is detected, DTCs B2021, B2031, B2032, and B2035 will not be detected.

Scheme 169

Scheme 170

The seat belt control ECU receives collision information from the driving support ECU and skid control ECU via CAN communication, and tightens the seat belt by operating the motor inside the front seat outer belt assembly.

When DTC B2001 is detected, DTCs B2015, B2026, and B2027 will not be detected.

When DTC B2006 is detected, DTCs B2020, B2031, and B2032 will not be detected.

The seat belt control ECU receives collision information from the driving support ECU and skid control ECU via CAN communication, and tightens the seat belt by operating the motor inside the front seat outer belt assembly.

When DTC B2002 is detected, DTCs B2026 and B2027 will not be detected.

When DTC B2007 is detected, DTCs B2031 and B2032 will not be detected.

The DTCs above are output during the seat belt control ECU's self diagnosis.

When DTC B2015 or B2016 is detected, DTCs B2026 and B2027 will not be detected.

When DTC B2020 or B2021 is detected, DTCs B2031 and B2032 will not be detected.

If the seat belt control ECU judges that there is a malfunction in its internal circuit as a result of self-diagnosis, or if the power source voltage (+B) is not input to the seat belt control ECU, this DTC will be stored.

Scheme 171

This DTC is output when a malfunction in the brake system is detected. This circuit consists of the skid control ECU and seat belt control ECU. Signals are sent from the skid control ECU assembly to the seal belt control ECU through the CAN communication line.

When DTC B2060 is detected, ABS system DTCs will also be detected.

The seat belt control ECU is connected to the main body ECU (multiplex network body ECU) through CAN communication.

The seat belt control ECU receives vehicle model information from the main body ECU (multiplex network body ECU) and determines whether the seat belt buckle switch information from the airbag sensor center is for the driver seat or the front passenger seat.

DTC B2064 is output when CAN communication with the main body ECU is normal and when communication is available, but the steering wheel position information is not set or varies.

The seat belt control ECU receives buckle switch condition information from the center airbag sensor through the CAN communication line and controls the pre-collision system.

This code is output when a buckle switch malfunction signal is received from the airbag system.

When DTC B2074 is detected, DTC B1655 is also output.

When DTC B2075 is detected, DTC B1650 is also output.

This DTC is stored when CAN communication between the driving support ECU and skid control ECU assembly is interrupted.

This circuit consists of the driving support ECU, skid control ECU assembly and seat belt control ECU. DTC B2085 is stored when the seat belt control ECU detects an interruption in CAN communication between the driving support ECU and skid control ECU assembly.

The seat belt control ECU receives collision information from the driving support ECU and skid control ECU assembly via CAN communication, and tightens the seat belt by operating the motor inside the front seat outer belt assembly.

When the driving support ECU detects a malfunction in the cruise control system, dynamic radar cruise control system, lane-keeping assist system, and pre-collision system ("Pre-Collision 2" part), or detects that the lane recognition camera sensor has not been adjusted, the malfunction information is sent to the seat belt control ECU, which outputs this DTC.

When DTC B2090 is detected, other DTCs output by the driving support ECU (cruise control system, dynamic radar cruise control system, lane-keeping assist system, Pre-Collision 2) are also output.

HINT

If the object recognition camera sensor is replaced with a new one and the adjustment of the lane recognition camera sensor has not been performed, DTC B2090 is output.

The driving support ECU uses the millimeter wave radar sensor to detect obstacles in front of the vehicle.

Based on this information, the driving support ECU calculates the risk of a collision and operates the pre-collision system when it determines that the risk is high.

When a new driving support ECU is installed, the new ECU receives and stores country specification information from the main body ECU (multiplex network body ECU). DTC C1A02 is stored when the driving support ECU receives the vehicle specification information from the main body ECU but cannot record it.

The driving support ECU uses the millimeter wave radar sensor to detect obstacles in front of the vehicle. Based on this information, the driving support ECU sends pre-collision control operation signals.

When the millimeter wave radar sensor is replaced with a new one, it acquires the country specification information from the driving support ECU. Also, when the driving support ECU is replaced with a new one, it receives country specification information from the main body ECU. When country specification information in the sensor, ECU and/or main body ECU do not match, DTC C1A0A is stored.

When the Lane recognition camera sensor is replaced with a new one, it acquires the country specification information from the driving support ECU. Also, when the driving support ECU is replaced with a new one, it receives country specification information from the combination meter. When country specification information in the Lane recognition camera sensor and driver monitor ECU do not match, DTC C1A0C is output.

If the sensor and vehicle country specification information are the same, and the combination meter and the driving support ECU country specification information are different, C1A0A is output.

The driving support ECU uses the millimeter wave radar sensor to detect obstacles in front of the vehicle. Based on this information, the driving support ECU sends pre-collision control operation signals.

When the driving support ECU receives information that there is a malfunction in the millimeter wave radar sensor, DTC C1A10 is output.

When the vehicle is determined to be moving in a straight line according to the signal from the yaw rate sensor, the millimeter wave radar sensor assembly performs a self-diagnosis to check whether its beam axis is misaligned. When it is determined that the vehicle in front is off to the side for a long period of time (10 hours at approximately 50 km/h (31 mph)), the millimeter wave radar sensor assembly determines that its beam axis is misaligned and DTC C1A11 is stored. Also, if the millimeter wave radar sensor assembly is installed at an angle with respect to the vehicle, the millimeter wave radar sensor assembly makes the same determination. After a new millimeter wave radar sensor assembly is installed, if the millimeter wave radar sensor beam axis adjustment is not performed, DTC C1A14 is stored.

This DTC is stored when the driving support ECU receives information that the lane recognition camera sensor assembly has an internal malfunction.

When it has been determined that the beam axis of the lane recognition camera sensor assembly has deviated, DTC C1A22 is stored.

After installing a new lane recognition camera sensor assembly, if camera beam axis adjustment is not performed, DTC C1A23 is stored.

When the distance from an object detected by the left and right camera greatly differs from the distance detected by the millimeter wave radar sensor assembly, DTC C1A25 is stored.

The driving support ECU uses the millimeter wave radar sensor, driver monitor camera and lane recognition camera sensor to detect obstacles in front of and behind the vehicle, and detect the direction that the driver's head is facing. Based on this information, the driving support ECU sends pre-collision control operation signals.

When the driving support ECU receives information that there is a malfunction in the driver monitor ECU, DTC C1A30 is output.

The driving support ECU uses the millimeter wave radar sensor, driver monitor camera and lane recognition camera sensor to detect obstacles in front of and behind the vehicle, and detect the direction that the driver's head is facing. Based on this information, the driving support ECU sends pre-collision control operation signals.

When the driving support ECU receives information that there is a malfunction in the driver monitor camera, DTC C1A31 is output.

When the driving support ECU receives a hybrid control system or SFI system malfunction signal, DTC C1A40 is stored.

The skid control ECU assembly receives brake control request signals from the power management control ECU and driving support ECU.

When the request signals received from the power management control ECU and driving support ECU are not consistent, the skid control ECU assembly determines that a malfunction has occurred and sends a malfunction signal to the driving support ECU.

If the driving support ECU receives a malfunction signal, DTC C1A41 is stored.

The skid control ECU assembly receives vehicle stability signals from the yaw rate sensor and sends the signals to the driving support ECU and ECM. If the skid control ECU assembly detects that the yaw rate sensor is malfunctioning, the skid control ECU assembly sends a malfunction signal to the driving support ECU and outputs DTC C1A46. Also, when DTC C1A46 is output, the skid control ECU outputs DTC C1234 at the same time.

When DTC C1A46 is detected, DTC C1234 is also output from the "ABS/VSC/TRAC".

The skid control ECU assembly receives steering rotation angle information from the spiral cable sub-assembly, and sends the information to the driving support ECU through the CAN communication line.

When DTC C1A47 is detected, DTC C1231 is also output from the "ABS/VSC/TRAC".

Based on pre-collision control, the driving support ECU informs to the driver to be careful. The driving support ECU performs this by sending a sounding signal to the skid control ECU assembly to sound the skid control buzzer.

When the skid control ECU assembly detects a malfunction in the skid control buzzer circuit, a malfunction signal is sent to the driving support ECU, and a DTC is output. Although the skid control ECU assembly sends a malfunction signal to the driving support ECU, the ABS does not output a relevant malfunction detection DTC.

The skid control ECU assembly outputs a stop light operation signal to the stop light control relay. When the skid control ECU assembly detects a malfunction in the circuit related to the stop light, it informs the driving support ECU via CAN communication and stores DTC C1A4B.

During vehicle-to-vehicle distance control mode, when the actual vehicle speed exceeds the set vehicle speed, such as on a steep downhill slope, etc., the driving support ECU sends a brake control signal to the skid control ECU assembly, and deceleration control is performed together with throttle valve control. When a malfunction occurs in the electronically controlled brake system which is controlled by the skid control ECU assembly, this DTC is stored.

The driving support ECU uses the front millimeter wave radar sensor, driver monitor camera and lane recognition camera sensor to detect obstacles in front of and behind the vehicle, and detect the direction that the driver's head is facing. Based on this information, the driving support ECU sends pre-collision control operation signals.

This DTC is output when a communication malfunction occurs between the sensors and ECUs that detect collisions, or between ECUs that perform the pre-collision control.

The driving support ECU receives pre-collision cancel on/off signals from the pre-collision system cancel switch assembly.

Scheme 172

This circuit supplies power to the seat belt control ECU when the power switch is on (IG).

Scheme 173

See also:
• DIAGNOSIS SYSTEM [03/2012 - ]
• REMOVAL [03/2012 - ]