The yaw rate sensor, lateral G sensor, longitudinal G sensor are packaged in the IMU(Inertial Measurement Unit). If the yaw velocity reaches the specific velocity after IMU detects the vehicle's yawing, the ESP(ESC) control is activated. IMU is installed in SRSCM and it interchanges signals with HECU through extra CAN line which is only used for communication between HECU and the IMU.
I If the difference between the estimated value from the other sensors and the measured value of the IMU message from SRSCM is larger than predefined value for predefined time, the failure is recognized.
Item | Detecting Condition | Possible cause | |
DTC Strategy |
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Signal monitoring | 1. Faulty IMU(SRSCM) 2. Improper installation condition | |
Case 1 | Enable Conditions |
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When the difference between estimated value and measured value of the yaw rate sensor or later G sensor is lager than Predefined value for specific time, ECU detects failure
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During standstill if Lateral G value is larger than 0.7g, and continue 2sec.
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During standstill if yaw rate value is larger than 6deg/s, and continue for 2sec.
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ECU compares the variation of wheel speed with the variation of G. If ECU detects G-Sensor signal stick, failure is detected. (4WD only)
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When velocity > 10kph(6.2mph) and the brake light switch is OFF, |G| > 0.5G for 20sec continuously (4WD only) | |
Case 2 | Enable Conditions |
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When the difference between estimated value and measured value of the lateral G sensor is lager than Predefined value for specific time, ECU detects failure | |
Case 3 | Enable Conditions |
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Yaw signal is smaller than predefined value when CBIT is transmitted
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Lateral G signal is smaller than defined value when CBIT is transmitted ※ CBIT : Commanded Built In Test | |
Case 4 | Enable Conditions |
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In case that Yaw & Lateral G Sensor Fail Flag is detected for defined time | |
Fail Safe |
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2WD vehicle : Inhibit the ESP(ESC) control and allow the ABS/EBD control, the ESP(ESC) warning lamp is activated
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4WD vehicle : Inhibit the ABS/ESP(ESC) control and allow the EBD control, the ABS/ESP(ESC) warning lamp is activated | ||
