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Would it be even possible/cost effective to retrofit an LT with the driver assitance packages required to make this work?
Anything is possible with enough time and money but it’s almost certainly less expensive to sell your current car and buy another with the packages. Even if you added the hardware and wiring/buttons from a junkyard car, you’d likely have to reprogram the ecu for it to work.
 

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Great videos! Thanks for posting. One thing I had not considered until watching the steering wheel adjust on its own... I wonder if using something like this will wear out the steering assist motor prematurely. The only reason I ask is that the motor they use to control the steering wheel may not have been designed to make constant adjustments given that it was only designed for rare LKA events. Any thoughts on that?

Mike
 

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the motor they use to control the steering wheel may not have been designed to make constant adjustments given that it was only designed for rare LKA events. Any thoughts on that?
I assume it is the same motor that is used for electric power steering normally. Why would they need a separate motor?
 

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I wonder if using something like this will wear out the steering assist motor prematurely. The only reason I ask is that the motor they use to control the steering wheel may not have been designed to make constant adjustments given that it was only designed for rare LKA events. Any thoughts on that?
I assume it is the same motor that is used for electric power steering normally. Why would they need a separate motor?
Well, you guys got me curious, so I cracked open the Service manual and it states...
The lane keep assist system is made up of the following components:​
  • Front view camera module
  • Lane Keep Assist switch/control indicator
  • Instrument cluster/Vehicle Direction Display
  • Radio
  • Safety Alert Seat (if equipped)
  • Yaw rate sensor
  • Electric power steering
And that when Lane Keep Assist uses it...
Electric Power Steering
The electric power steering uses a torque sensor to detect driver inputs and relays that information to the frontview camera module. The electric power steering is used to provide steering push back.​
There is two stages of warning/intervention for the driver: The first stage is the steering push back, if the lane keep assist system detects that the vehicle will cross the lane marking despite it is intervening, a second stage warning shall be issued. The second stage warning is a chime or a haptic seat vibration, if equipped with haptic seats. If a haptic seat vibration is used as stage 2 warning, the vibration shall take place on the side of the seat, where the lane departure happened.​

So, I checked and the "K43 Power Steering Control Module" description and operation says...
The electric power steering system reduces the amount of effort needed to steer the vehicle. The system / uses the body control module, power steering control module, torque sensor, discrete battery voltage supply circuit, electric power steering motor, serial data bus, and the instrument panel cluster message center to perform the system functions. Any electric power steering components diagnosed to be malfunctioning requires replacement of the steering column assembly, also known as the electric power steering assembly.​
Torque Sensor
The power steering control module uses a torque sensor as it's main input for determining the amount of steering assist. The steering column has an input shaft, from the steering wheel to the torque sensor, and an output shaft, from the torque sensor to the steering shaft coupler. The input and output shafts are separated by a torsion bar, where the torque sensor is located. The sensor consists of a compensation coil, detecting coil and 3 detecting rings. These detecting rings have toothed edges that face each other. Detecting ring 1 is fixed to the output shaft, detecting rings 2 and 3 are fixed top the input shaft. The detecting coil is positioned around the toothed edges of detecting rings 1 and 2. As torque is applied to the steering column shaft the alignment of the teeth between detecting rings 1 and 2 changes, which causes the detecting coil signal voltage to change. The power steering control module recognizes this change in signal voltage as steering column shaft torque. The compensation coil is used to compensate for changes in electrical circuit impedance due to circuit temperature changes from the electrical current and voltage levels as well as ambient temperatures for accurate torque detection.​
EPS Motor
The electric power steering motor is a 12-volt brushed DC reversible motor. The motor assists steering through a worm shaft and reduction gear located in the steering column housing.
Power Steering Control Module
The power steering control module uses a combination of torque sensor inputs, vehicle speed, calculated system temperature and the steering calibration to determine the amount of steering assist. When the steering wheel is turned, the power steering control module uses signal voltage from the torque sensor to detect the amount of torque being applied to the steering column shaft and the amount of current to command to the electric power steering motor. The power steering control module receives serial data from the engine control module to determine vehicle speed. At low speeds more assist is provided for easy turning during parking maneuvers. At high speeds, less assist is provided for improved road feel and directional stability. In this mode the power steering control module will limit the amount of current commanded to the electric power steering motor which reduces steering assist levels. The power steering control module also chooses which steering calibration to use when the ignition is turned ON, based on the production map number stored in the body control module. The power steering control module contains all 8 of the steering calibrations which are different in relation to the vehicles RPOs. The power steering control module has the ability to detect malfunctions within the electric power steering system. Any malfunction detected will cause the instrument panel cluster message center to display a warning message.​
So, I believe GJetson is right. The same electric motor that gives us power assisted steering is also the one that turns the wheel, yet it is all part of GM Part 42608297 - Column Asm-Steering (W/ Asst Motor) so it is a pricey replacement part ($750) if that 12v motor did burnout/overheat. However, you could potentially rebuild your steering column for less.
 

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Discussion Starter #28
Great videos! Thanks for posting. One thing I had not considered until watching the steering wheel adjust on its own... I wonder if using something like this will wear out the steering assist motor prematurely. The only reason I ask is that the motor they use to control the steering wheel may not have been designed to make constant adjustments given that it was only designed for rare LKA events. Any thoughts on that?

Mike
Good question and I don't have the answer but I know Volt owners have been using this setup for 2-3 years and I have not heard of a failure.

It is honestly not great for in-town driving use but for hwy/interstate - it is fantastic - I assume the corrections/torque requirements are significantly less at speed.
 
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