Eliminating TC/AH 100%
03-28-2014, 09:17 AM
#22
Melting Slicks
Thread Starter
03-31-2014, 04:03 PM
#23
Safety Car
There are instances I have seen here on the forum where the yaw sensor mounting is at fault. Have you checked that as well?
To clear up some confusion, there is only one ABS/TCS/AH module. It is referred to as the EBCM on the C5 and is located between the radiator and PS pump. This module controls all three functions based on sensor data incoming from other parts of the vehicle.
Primarily, these include the four WSS (wheel speed sensors) and the IMU (inertial measurement unit) which includes the yaw sensor as well as G sensors. Also, as stated above, the SAS (steering angle sensor) and vehicle speed are used.
AH works by calculating yaw based on steering angle and vehicle speed, then compares it to measured yaw from the sensor. If they don't match, you are under- or over- steering and individual brakes are applied to counter. Therefore, if the SAS is faulted (or unplugged) it will disable AH as this is a required input.
ABS can use only WSS, which is why it should still function without the SAS. This is a "fail safe" mode but performance could be reduced. Even though not required, other vehicle information such as deceleration g's and yaw can enhance ABS performance.
To clear up some confusion, there is only one ABS/TCS/AH module. It is referred to as the EBCM on the C5 and is located between the radiator and PS pump. This module controls all three functions based on sensor data incoming from other parts of the vehicle.
Primarily, these include the four WSS (wheel speed sensors) and the IMU (inertial measurement unit) which includes the yaw sensor as well as G sensors. Also, as stated above, the SAS (steering angle sensor) and vehicle speed are used.
AH works by calculating yaw based on steering angle and vehicle speed, then compares it to measured yaw from the sensor. If they don't match, you are under- or over- steering and individual brakes are applied to counter. Therefore, if the SAS is faulted (or unplugged) it will disable AH as this is a required input.
ABS can use only WSS, which is why it should still function without the SAS. This is a "fail safe" mode but performance could be reduced. Even though not required, other vehicle information such as deceleration g's and yaw can enhance ABS performance.
03-31-2014, 06:13 PM
#24
Racer
My SAS is intermittently faulting, causes my c5 to pull to the left. Was interesting the first time it happened. Didn't figure it out until it finally set a code.