2019 GM 1500 trucks brake info, no more master cyl.

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Thought this was interesting. Looks like vehicle complexity is getting crazy. Brake System Overview Note: ZF TRW’s Integrated Brake Control is a 1-piece module that eliminates the master cylinder, vacuum pump and associated hoses while incorporating electronic stability control, traction control and an electric motor to push hydraulic fluid to brakes at all four corners. The module is 13 lbs. (6 kg) lighter than the total weight of a conventional system and only requires about half the packaging space underhood. The vehicles are equipped with a ZF TRW Integrated Brake Control (IBC), also known as a Brake System Control Module. The IBC is an electromechanical device that interprets and converts driver input and provides a corresponding hydraulic pressure output to activate a standard brake system according to driver demand. In an event of no electrical energy or failure condition the driver’s input is mechanically converted to a hydraulic pressure output. Use DOT 4 Hydraulic Brake Fluid (GM Part No. 19299570, in Canada 19299571). Electrical Component Operation The Body Control Module (BCM) monitors the brake pedal position sensor signal when the brake pedal is applied and sends a high speed serial data message to the Brake System Control Module indicating the brake pedal position. The following electrical components are used: Wheel Speed Sensors: Equipped with unique directional wheel speed sensors that can detect wheel direction as well as zero wheel speed. The wheel speed sensors are Active sensors that receive a 12 V power supply from the Brake System Control Module and returns an output signal to the module. As the wheel spins, the wheel speed sensor sends the Brake System Control Module a DC square wave signal. The Brake System Control Module uses the frequency of the square wave signal to calculate the wheel speed. Multi-Axis Acceleration Sensor: The yaw rate, lateral acceleration and longitudinal acceleration sensors are combined into one multi-axis acceleration sensor, internal to the inflatable restraint sensing and diagnostic module. The Brake System Control Module receives serial data message inputs from the three sensors and activates Stability Control and Hill Hold Start Assist functions depending on multi-axis acceleration sensor input. Multifunction Switch: The traction control switch is a multifunction momentary switch. The traction control and stability control are manually disabled or enabled by pressing the traction control switch. Steering Wheel Angle Sensor: The Brake System Control Module receives serial data message inputs from the steering angle sensor. The steering wheel angle sensor signal is used to calculate the intended driving direction. The sensor is an internal part of the power steering gear. Transmission Control Module: The Brake System Control Module receives high speed serial data message inputs from the transmission control module indicating the gear position of the transmission for Hill Start Assist and Hill Hold functions. Vehicle Brake Enhancement Systems Depending on options, the following vehicle brake enhancement systems are provided: Power-Up-Self Test: The Brake System Control Module performs the first phase of the power-up-self test when the ignition is first turned ON. This phase consists of internal testing of the Brake System Control Module and electrical tests of system sensors and circuits. Antilock Brake system : ABS provides the active control/modulation of brake fluid hydraulic pressure to the front and/or rear brake corner subsystems (brake torque control) to preclude wheel lock-up and enhance tire-to-road longitudinal braking traction. Avoidance of wheel lock-up provides the driver with the ability to maintain vehicle stability and steerability and minimizes vehicle stopping distance. Brake Assist: Brake Assist provides additional brake pressure over the pressure provided by the conventional brake apply system. Panic Brake Assist: Panic Brake Assist will apply the brakes more quickly when a panic brake situation is determined. Panic Brake Assist detects that the driver intent is to stop the vehicle as quickly as possible, but the driver does not apply sufficient brake pressure to do so. The feature will detect the driver intent then actively apply brake pressure to maximum pressure, activating the ABS system and stopping the vehicle as quickly as possible. Hydraulic Fade Compensation: Based on a brake disc/pad temperature estimate, driver applied master cylinder pressure and vehicle deceleration rate, Hydraulic Fade Compensation will increase brake system pressure above driver applied brake pressure when the brake system determines a gross fade condition. Rear Brake Boost: Rear Brake Boost provides rear hydraulic brake assist to ensure that all four corners are achieving maximum braking during ABS. When vehicle loading is heavily rear axle biased the rear brakes may not utilize all of the available road adhesion. Rear Brake Boost will provide additional pressure to the rear brakes when the front brakes ABS are activated and the rear wheels have low slip. Electronic Pre-Fill: Electronic Pre-Fill is used to reduce the brake response time when the driver quickly releases the accelerator pedal. This is also used to support the use of low drag calipers.
 
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1,861
Location
missouri
Who boy. They have been working towards this for a long time. There have been lots electric power assisted brakes since 2000. for example my 2002 BMW motorcycle had power assisted full anti lock brakes, I personally had no problems but many did. That system did have unassisted back up. The replacement abs module is over 2k so many got converted to normal brakes. That sounds like the system here. If I had one I would carefully and completely flush all brake fluid every 2 years minimum. Brake fluids do differ in anti-corrosion additives. I would use only premium fluids, and GM fluid is very good. It is possible someone like Module masters will learn how to rebuild them. You can hope. Rod
 
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8,764
Location
Illinois
Sounds nice and expensive to work on. A plan to keep the dealer's service department raking in the cash? And just wait until it starts giving problems... after the warranty expires. I just can't wait.
 

AVB

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1,461
Location
Georgia
Chrysler works basically the same way, they just haven't removed the master cylinder yet. It is mostly there just for the pedal feel.
 
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2,702
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USA
Originally Posted By: Rat407
In an event of no electrical energy or failure condition the driver’s input is mechanically converted to a hydraulic pressure output.
How would that work without some sort of cylinder?
 
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Worst Case, Ontario
Originally Posted By: ragtoplvr
The replacement abs module is over 2k so many got converted to normal brakes. That sounds like the system here.
The system is very advanced, and has a lot of cool features to increase safety and performance, but ABS pumps are super expensive, and with this MC-less braking system, you are going to tack on another $2000+ module. Pretty sweet though, I wonder if you will be able to mod it to access over 100% braking power?
 
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23,787
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MA, Mittelfranken.de
As this system ages it sounds like it will be a nightmare. In the rust belt I anticipate lots of failures around the 5 yr mark, just too much to go wrong. It will be an absolute bugger to diagnose and repair if its anything more than the scan tool can display eg wiring to a sensor. Going through that that now with a 2011 Dodge Caliber no crank situation, lots and lots wiring issues all over the place, 6 hrs in and no end in sight.
 

CT8

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15,409
Location
Idaho
Originally Posted By: Trav
As this system ages it sounds like it will be a nightmare. In the rust belt I anticipate lots of failures around the 5 yr mark, just too much to go wrong. It will be an absolute bugger to diagnose and repair if its anything more than the scan tool can display eg wiring to a sensor. Going through that that now with a 2011 Dodge Caliber no crank situation, lots and lots wiring issues all over the place, 6 hrs in and no end in sight.
Well spoken by the master !!!
 
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34,440
Location
NY
Sounds cool, and expensive. Since this is probably another technology that will be hard to avoid in the not so distant future I'll let the early adopters iron out the bugs, and report back. By the time I'm ready for another new vehicle the system should be perfected, and hopefully an improvement over what I currently have.
 
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558
Location
Indiana
Well if its going to get screwed up, GM will be the ones to do it. With that being said I remember all the apocalyptic predictions back when "Fuel Infection" came out. IIRC the Fox Body LSC had an ABS unit that used an accumulator and was an expensive system to repair back in the 90s/early 2000s. The thing about these redneck status symbol pickup trucks being sold nowadays, the original owner isn't likely going to have it in 10 years, let alone 20. GM, nor any other manufacturer does not care about repair cost or serviceability down the line. Its cheaper, lighter and quicker for them to assemble. And as always, if there is a need for parts support down the road there will be a company willing to step in and provide that support. (I know that there are some trucks used for work, but lets be honest here)
 
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'murica
Trav is exactly right. I’ll add this: with automakers now wanting to build cars using off-the-shelf components and systems like this, we’re going to see an increase in industry-wide recalls (e.g. Takata’s recent debacle).
 
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5,091
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USA
I laugh when GM buyers will justify their (usually) Chevrolet truck purchase with: "I always buy a Chevy because they change the least of the big 3" "I buy Chevy because its the easiest to work on..least complicated" "I buy a Chevy because they really haven't changed much since 1955..." Wait until some old [censored] finds out 4 or 5 years from now what its going to cost to get his brakes back....and wait until 7-8 years out when GM obsoletes the part making it non-obtainum....LOL
 

JTK

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12,869
Location
Buffalo, NY
Diagnosing and repairing? The way I see it, this will be like an ABS module. If it doesn't work, it gets replaced at great expense. You had to figure it was a matter of time before mechanical brakes were replaced by "brake by wire". Easier for all the computer controlled safety systems buyers like.
 

CT8

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15,409
Location
Idaho
Originally Posted By: JTK
Diagnosing and repairing? The way I see it, this will be like an ABS module. If it doesn't work, it gets replaced at great expense. You had to figure it was a matter of time before mechanical brakes were replaced by "brake by wire". Easier for all the computer controlled safety systems buyers like.
My F150 has an electric e brake i don't know how it works though.
 
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CA
Can the mods move this very informative thread to a section that is more appropriate and will get more exposure? "Science and Technology of Oils and Lubricant Additives" ?????
 
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4,450
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Pittsburgh,PA U.S.A.
Braking systems that advanced may be something most vehicles will use in the near future, but there may come a time when they will become obsolete. Someday (maybe not in our life times) after autonomous vehicles are really perfected and have been in use long enough to prove that crashes no longer happen, it will not be worth it to make the breaking system more complicated to shave off every 1/10000 of a second travel, inches of travel, during breaking, and breaking systems that complicated will be obsolete. Also, someday (maybe not in our life times) after autonomous vehicles have really been perfected, bumpers, crumple zones, and air bags will be obsolete.
 
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