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Re: Power steering quit working (again)

Posted: Mon Nov 13, 2017 5:45 pm
by s/c'd cav
its not a cheap , but it is possible , i just dont know how the computers will enjoy it ?

also not sure if the hydraulic assit rack will bolt into the subframe for the electric assit rack or not , which would cost more and add to time to do it

Re: Power steering quit working (again)

Posted: Mon Nov 13, 2017 6:54 pm
by major_ppv_fan
Yeah, so GM dealer service center says "if it's the gear and motor it would be [roughly $1700] to replace". (What motor???)
Not covered by recall or warranty. Quality.

Also, GM Customer Relations number is automated and hangs up on you if you ask to speak to a human about your issue.
:x :x :x :x :x :x :x

Re: Power steering quit working (again)

Posted: Mon Nov 13, 2017 7:59 pm
by s/c'd cav
the motor is a electrical motor , which is what gives the assit for the steering

Re: Power steering quit working (again)

Posted: Mon Nov 13, 2017 8:31 pm
by major_ppv_fan
Yeah, I've been trying to figure out what the part name/part number is so I could research it some more.
Truly wish I had a set of repair manuals for the 2014.

Re: Power steering quit working (again)

Posted: Mon Nov 13, 2017 8:45 pm
by major_ppv_fan
Probably looks something like this, but I cannot seem to locate it in any online parts catalogue.

Re: Power steering quit working (again)

Posted: Tue Nov 14, 2017 3:58 am
by s/c'd cav
the rack is #1 , the motor is part of it , on the front side in that pic

Re: Power steering quit working (again)

Posted: Tue Nov 14, 2017 4:06 am
by s/c'd cav
major_ppv_fan wrote: AH, so I could convert my '14 from electric to hydraulic power-assisted steering?
that would be entirely your call ''

Re: Power steering quit working (again)

Posted: Tue Nov 14, 2017 8:49 am
by smwalker
my appoligies I got you thinking it was a pump. I thought it was an electric motor that acted like a pump, when it is really a motor that acts directly on the rack. Descrition from the service manual and it does not seem like the motor or internal belt is serviceable so the entire rack has to be replaced each time. Wonder if any of the rebuild houses are rebuilding these yet??

Description and Operation

Power Steering System Description and Operation (Belt Drive Electronic Power Steering)


The belt driven electronic power steering system consists of the following components:

1. The integrated electromechanical power steering unit, containing the power steering control module, its sensors, the power steering
motor, a belt drive and a ball nut mechanism
2. The steering gear (rack and pinion)

The belt driven electric power steering system reduces the amount of effort needed to steer the vehicle utilizing the power steering control module to control the power steering motor to maneuver the steering gear. The power steering control module also uses a combination of the torque sensor, motor rotational sensor, battery voltage circuit and GMLAN serial data circuit to perform the system functions. The power steering control module monitors vehicle speed and engine speed from the engine control module via the GMLAN serial data circuit to determine the amount of steering assist needed to steer the vehicle. At low speeds more assist is provided for easy turning during parking maneuvers. At higher speeds less assist is provided for improved road feel and directional stability.

The power steering control module uses a combination of the torque sensor, motor rotational sensor, vehicle speed, and calculated system temperature inputs to determine the amount of assist needed. The power steering control module continuously monitors the digital torque sensor's torque and index current signals. As the steering wheel is turned and torsional twist is applied to the steering shaft, the steering input and output shafts are monitored via the torque signal circuit and then processed by the power steering control module to calculate the steering torque. The voltage signals of the motor position sensor and the digital torque sensor's index current signal are both processed by the power steering control module to detect and calculate the steering wheel angle.

The power steering control module responds to the change in the digital torque sensor signals as well as the motor rotational sensor's voltage signals by commanding current to the power steering motor. The power steering control module controls the motor drive circuit to drive the alternating current motor. The power steering control module & motor assembly is attached to the base of the steering gear housing and applies power assist directly to the rack with a belt drive and a ball nut mechanism to maneuver the rack laterally depending on the direction the steering wheel is turned.

The power steering control module has the ability to calculate an internal system temperature to protect the power steering system from damage caused by high temperature. To reduce a high system temperature, the power steering control module will reduce the amount of current commanded to the power steering motor, which reduces the amount of steering assist. The power steering control module has the ability to detect malfunctions within the electric power steering system. Any malfunction detected that disables steering assist will cause the SERVICE POWER STEERING message to be displayed on the driver information center.

Re: Power steering quit working (again)

Posted: Tue Nov 14, 2017 8:58 am
by smwalker
Wiring diagram. 125 Amp fuse at the alternator! This system is power hungry!!

Image

Re: Power steering quit working (again)

Posted: Thu Nov 16, 2017 5:14 am
by major_ppv_fan
smwalker wrote:The power steering control module has the ability to detect malfunctions within the electric power steering system. Any malfunction detected that disables steering assist will cause the SERVICE POWER STEERING message to be displayed on the driver information center.
Yeah... I've never had a single SERVICE POWER STEERING message in the DIC - neither this time nor the last time it was failed (when I purchased the vehicle and it had not yet been through the original recall service). Electric power steering was definitely completely dead when I purchased it - and it feels like it's very-nearly dead this time 'round. Yeah, I know - not sure how that's even possible, but to describe further it felt "heavier" the first time around and it feels like it's not quite as "heavy" this time but it's def not working correctly. Hope that makes sense.

¯_(ツ)_/¯