HELP w 2016 Chevy Malibu Limited
Can someone please look at these photos and tell me what I need to be doing...

History:
It kept feeling like I had a brake sticking or stuck after I would drive the car 15-30 mins.
My brake lights would remain on when I let my foot off the brake.
Stabili Trak and BrakeAssist lights illuminated in the dash - Individual diagnostic scan showed left, rear wheel speed sensor.
Left rear wheel speed sensor replaced, the lights in the dash went away but issue continued. - Individual diagnostic scan showed the sensor being "erratic"
Left rear wheel speed sensor replaced again (first one was generic so thought maybe) and the wheel hub assembly - issues continued
Issues were progressing and intermittent
Now all 4 brakes drag intermittent, usually after driving 15-30 mins, with the wheels reaching 240 degrees at times.
Sometimes I can feel the brakes pulsing.
Car floats all over the road.
Doens't feel like my traction control is working
No lights ever came back on.
Both batteries were also replaced sometime during all of this.

Taken it to an individual shop and was diagnosed it as the brake booster-NOT THE ISSUE
Had an individual scan performed and he reported EBCM. SEE PICTURE-only got one
I filed a claim with GM due to same symptoms as EBCM Recall
Took it to a certified chevy dealership and they reported a false diagnosis (rust on back brakes) to GM and had my claim closed. Refused to give me the full diagnostic scan report but I was able to get some of it from the new kid working there. SEE attachment

In the scan it gives a part number #22863598 which is the Anti-Lock Brake Pump Control Module which is made of two parts from my understanding? The Module and then the Pump.
I was going to send the module in to be rebuilt but after sending the pictures to them of the scans, someone suggested it being the pump and not the module.

I need my car fixed and can't afford to be gambling on parts. Can anyone give me some clarity? It would be truly appreciated as I desperately need my vehicle to get my son to apts, school, and therapies.

There'* a lot to go through here, so breaking it down in pieces:

How many miles on it?

How many miles have you owned it?

Any recent damage?

Any flood damage?

Any recent surgery besides what you've already described here?

What region does it live in?

Has it always lived here?

If not, where else has it lived?

Why do you say this? Does the car feel like it is working really hard to do everything?

​​​​​​​This tells me that the brake pedal isn't retracting all the way and/or the Brake Pedal Position Sensor is bad and/or needs to be re-learned. This can sometimes come and go based on temperature, weather, vibrations, the mood of your preferred deity, etc.

While this is happening, can you pull the brake pedal up hard and make the brake lights go off? Can you push down on the pedal slightly and make the brake lights go off?

​​​​​​​​​​​​​​This will sometimes happen when it thinks you're driving down the road with your foot on the brake because of the Brake Pedal Position Sensor issue above. It can happen for other reasons as well, such as . . .

​​​​​​​Assuming it showed that the LR wheel sensor was bad or erratic, but if you have a complete description, that'd help.

I'm curious: Who is doing all of this replacing of parts? Is this at a shop?

If you look on a scope, does the waveform look erratic?

Which wheels get that hot?

After driving how far how fast?

After coasting to a stop or braking hard to a stop?

How is this being measured?

Where is this being measured (rotor, wheel, etc.)?

Good symptom to know about. Makes sense if the brakes are hot a lot, let'* fix other issues first.

What do you mean by this? Does it need an alignment as well? . . . or shocks? . . . or . . . ?

What do you mean by this? Is a tire scratching or spinning a lot while accellerating?

In what condition? Accelerating hard? Accellerating hard while turning a corner on sand? Etc.?

Both batteries?

How old were they?

What were the test results for them?

How was this diagnosed?

How do you know this is not the issue?

Reported EBCM what? . . . like what about it? Some kind of error? . . . or failed completely? . . . or . . . ?

Who performed the individual scan? What tool did they use to perform the individual scan?

What codes were stored?

What were any other readings?

Was there rust on the back brakes?

Did the rust get removed?

If "yes, the rust got removed", did this solve the symptom?

If you answered yes, yes, no, then it would seem that the issue should not have been closed. If they claim the complaint is caused by the rust, and they remove the rust, and the complained condition still exists, then their diagnosis would be incorrect.

What was their reason for refusing to give you the full diagnostic scan report?

You paid for the diagnosis to be done, right?

Okay . . . ?

Why?

Have we clearly diagnosed the pump as bad?

Who is "someone"?

Why did they suggest this?

Clarity will come from properly diagnosing and repairing all of the issues here as they are needed. Right now, it sounds like you have the clarity that a ping-pong ball would have if it took its Malibu to get diagnosed by several different folks that all condemned different parts of the car.

I'll start helping with this now. You've already replaced stuff, gotten several different diagnoses, and are lining up to replace more stuff. These cars aren't so poor that all of this stuff would be going bad on it at once (unless it was flooded or something). This tells me that the current combination of all diagnostics, parts condemnations, and repairs are likely not accurate.

Here'* where I'd start: I haven't heard that the brake lights staying on ever got repaired. I'd fix that issue first. It is likely the Brake Pedal Position Sensor as described above. It just could be causing all of this.

There'* a lot to go through here, so breaking it down in pieces:

Quote:
Originally Posted by Stephanie
2016 Chevy Malibu Limited
How many miles on it? 163,000 (yes I know. It'* time to retire but I have a child with special needs and I've been out of work since his birth and won't be financially able to do so until I can hopefully get him in school full time)

How many miles have you owned it? boutht it at 33,000 miles

Any recent damage? no.

Any flood damage? no

Any recent surgery besides what you've already described here? just what I've described here and brake pads. a wheel bearing several years ago

What region does it live in? southern Il

Has it always lived here? yes

If not, where else has it lived?

Quote:
Originally Posted by Stephanie
It kept feeling like I had a brake sticking or stuck after I would drive the car 15-30 mins.
Why do you say this? Does the car feel like it is working really hard to do everything? car felt like it was being held back. pulls


Quote:
Originally Posted by Stephanie
My brake lights would remain on when I let my foot off the brake.
This tells me that the brake pedal isn't retracting all the way and/or the Brake Pedal Position Sensor is bad and/or needs to be re-learned. This can sometimes come and go based on temperature, weather, vibrations, the mood of your preferred deity, etc. the light would turn off if i pulled up on the brake pedal but i think it was retracting all the way bc there was never any space when pulling up on it. i kinda was just putting weight up. a relearn was performed on the brake pedal . when it was performed i felt like it mighit of helped for like a week?

While this is happening, can you pull the brake pedal up hard and make the brake lights go off? Can you push down on the pedal slightly and make the brake lights go off? i would just have to put my foot under it and put wieight upwards on it. never any wiggle room or anything.

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Quote:
Originally Posted by Stephanie
Stabili Trak and BrakeAssist lights illuminated in the dash
This will sometimes happen when it thinks you're driving down the road with your foot on the brake because of the Brake Pedal Position Sensor issue above. It can happen for other reasons as well, such as . . .when these lights illuminated i was driving through town with 35-40 speed limit? When these illuminated, a indipendednt scan was performed and thats when it said left rear wheel speed sensor.

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Quote:
Originally Posted by Stephanie
Individual diagnostic scan showed left, rear wheel speed sensor.
Assuming it showed that the LR wheel sensor was bad or erratic, but if you have a complete description, that'd help. I do not. I didn't personally read it. a friend of mine is a mechanic and has the electronics to do the diagnostic scans. I could ask him to look at the history.

Quote:
Originally Posted by Stephanie
Left rear wheel speed sensor replaced, the lights in the dash went away but issue continued. - Individual diagnostic scan showed the sensor being "erratic"
Left rear wheel speed sensor replaced again (first one was generic so thought maybe) and the wheel hub assembly - issues continued
Issues were progressing and intermittent
I'm curious: Who is doing all of this replacing of parts? Is this at a shop? Independent mechanic on his time outside of work

If you look on a scope, does the waveform look erratic? I don't have a clue what your talking about here.

Quote:
Originally Posted by Stephanie
Now all 4 brakes drag intermittent, usually after driving 15-30 mins, with the wheels reaching 240 degrees at times.
Which wheels get that hot? I've only had them get that hot once that i"m aware of and it was all 4 of them. However i never checked them until this time. The car was back and fourth all over the road that day and I could feel the car was being held back. So on my way home i stopped at my fathers and he checked them bc he thinks im crazy and dont know what im talking about.

After driving how far how fast? I'm not certian but i believe it was around 40 miles that day probably at 60-65

After coasting to a stop or braking hard to a stop? when it is having this issue, if i let my foot off the gas the car immediately slows down, you can tell that the brakes are already being applied without putting your foot on the brake. Like if i were to stop then let my foot off the gas, my car wouldn't roll. and yes its taking longer for the car to stop.

How is this being measured? the temp? with a "A'MES Instruments" Infrared thermometer

Where is this being measured (rotor, wheel, etc.)? rotor

Quote:
Originally Posted by Stephanie
Sometimes I can feel the brakes pulsing.
Good symptom to know about. Makes sense if the brakes are hot a lot, let'* fix other issues first.

Quote:
Originally Posted by Stephanie
Car floats all over the road.
What do you mean by this? Does it need an alignment as well? . . . or shocks? . . . or . . . ? no, when the brakes are dragging or being applied, the car is just back and fourth all over the road.only way i can explain it is like when somethigns holding my car back but im still applying the gas and there going against each other, eventually the cars gonna veer one way or the other. its kinda like that. going from line to line. Doens't need an alignment, had one the last time i got new tires put on.

Quote:
Originally Posted by Stephanie
Doens't feel like my traction control is working
What do you mean by this? Is a tire scratching or spinning a lot while accellerating? tires spinning

In what condition? Accelerating hard? Accellerating hard while turning a corner on sand? Etc.? when backing out of the driveway slightly downhill under 10 mph id say? or sliding all over the place in he recent snow. not stopping, tires spinning non stop. slow speeds

Quote:
Originally Posted by Stephanie
Both batteries were also replaced sometime during all of this.
Both batteries? the aux battery in the trunk and the other one under the hood.

How old were they? old-first time i replaced both of them and ive had the car since 2017

What were the test results for them? idk

Quote:
Originally Posted by Stephanie
Taken it to an individual shop and was diagnosed it as the brake booster
How was this diagnosed? idk. he said he wasn't certain but thats what he was thinking ti was but didn't want to gamble on a 700 repair. It'* not the brake booster.

Quote:
Originally Posted by Stephanie
-NOT THE ISSUE
How do you know this is not the issue? bc there is no hissing sound. i did all the DIY at home brake pumping tests.

Quote:
Originally Posted by Stephanie
Had an individual scan performed and he reported EBCM.
Reported EBCM what? . . . like what about it? Some kind of error? . . . or failed completely? . . . or . . . ? He just said its the EBCM. then he looked up how much a module would be. the only part of that scan i saw or have is the one picture of the "Launch" scan in the picture above

Who performed the individual scan? What tool did they use to perform the individual scan? a mechanic who has their own scan tool outside of work. first one was that launch pictured. im uncertain on the other one.
What codes were stored? Im uncertain on the independent scans. the onec that the dealership gave me were:
DTC Code: Symptom Byte: DTC Description: Symptom Description: status:
U0422 71 Invalid Data Received From Body Control Module Invalid Data current
B2575 01 Headlamps Control Circuit short to battery passed and failed
B2575 04 Headlamps control circuit open current
B3101 00 keyless entry data link circuit ------ passed and failed
B317A 02 passenger window switch short to ground passed and failed
C0750 29 Left front tire pressure sensor too few pulses current
C0755 29 right front tire pressure sensor too few pulses current
C0760 03 left rear tire pressure sensor low voltage current
C0760 29 left rear tire pressure sensor too few pulses current
C0765 29 right rear tire pressure sensor too few pulses current
Not sure if they gave me all of them?
What were any other readings?

Quote:
Originally Posted by Stephanie
Had an individual scan performed and he reported EBCM. SEE PICTURE-only got one
I filed a claim with GM due to same symptoms as EBCM Recall
Took it to a certified chevy dealership and they reported a false diagnosis (rust on back brakes) to GM and had my claim closed.
Was there rust on the back brakes? the report was bogus. completely false. he called me back after he did the diagnostic scan and said no codes came up, no lights are on, nothings wrong with it and to come get it. I stated to him that the problem is intermittent and they need to drive it then check again. the second time he called me he said yeah i drove it and i heard what your hearing, its the back brakes making that sound. I NEVER REPORTED A SOUND BC IT WASN'T MAKING ANY SOUNDS.

Did the rust get removed? yes

If "yes, the rust got removed", did this solve the symptom? no...thats why im here asking the question above

If you answered yes, yes, no, then it would seem that the issue should not have been closed. If they claim the complaint is caused by the rust, and they remove the rust, and the complained condition still exists, then their diagnosis would be incorrect. no it shouldn't of been closed. he should have never let me drive it home and i stated all of this to gm customer service. i stated how the car wasn't safe to drive. and she said mam, he wouldn't let you drive it if it wasn't safe. on the scan screenshots that the new kid sent me in the link above, you can see that there is a uncommanded brake pressure. rust doesn't create hydraulic pressure

Quote:
Originally Posted by Stephanie
Refused to give me the full diagnostic scan report but I was able to get some of it from the new kid working there.
What was their reason for refusing to give you the full diagnostic scan report? I kept asking for them to send to email it to me so i could send it to GM bc thats what they were asking for. thats they only reason i had my car at the dealership was to follor gms protocol bc they led me to believe that they could do goodwill repair. but they said they would give it to me when i picked the car up. i stated i wasn't picking the car up until i got the report to gm and they advised me what tto do. it came down to me picking my car up, driving it home with brakes dragging. they tried holding my keys bc i refused to pay for the scan. but told the kid that they werent legally allowed to do so.

You paid for the diagnosis to be done, right? i was going to, yes. until they made the false claim to gm and refused to give me the report. so no. they tried to charge me for it and wouldnt give me my keys. then the kid laid them down to type somehing in his computer and i told him he wasn't legally allowed to keeo them and i reached behind the counter and grabbed my keys. then asked if i could get out of the fence where my car was parked.

Quote:
Originally Posted by Stephanie
In the scan it gives a part number #22863598 which is the Anti-Lock Brake Pump Control Module which is made of two parts from my understanding? The Module and then the Pump.
Okay . . . ?ok so is it giving me that part number bc thats where the issue is or why is that part number appearing? i don't know how to read these scans? and my questions in the thread above is if the issue is the pump or the module. bc you can replace just the pump and not the module so in my case if it were the pump, i could replace the pump and keep my modle and not have to program it. but if its the module, then i either have to replace it and get it programmed or get it rebuilt. i dont have the finacnial ability to gamble

Quote:
Originally Posted by Stephanie
I was going to send the module in to be rebuilt but after sending the pictures to them of the scans
Why? bc everything was pointing to the module???

Have we clearly diagnosed the pump as bad? no. im trying to figure this out outside of a shop bc i don't have the money for this.

Quote:
Originally Posted by Stephanie
someone suggested it being the pump and not the module.
Who is "someone"? The customer service rep or whoever approved my custom repair request at UpFix.

Why did they suggest this? idk. i provided them the same pictures as i did above in the link and they said that they can repair the modle but not the pump and it sounded like a pump issue to him

Quote:
Originally Posted by Stephanie
I need my car fixed and can't afford to be gambling on parts. Can anyone give me some clarity? It would be truly appreciated as I desperately need my vehicle to get my son to apts, school, and therapies.
Clarity will come from properly diagnosing and repairing all of the issues here as they are needed. Right now, it sounds like you have the clarity that a ping-pong ball would have if it took its Malibu to get diagnosed by several different folks that all condemned different parts of the car.

I'll start helping with this now. You've already replaced stuff, gotten several different diagnoses, and are lining up to replace more stuff. These cars aren't so poor that all of this stuff would be going bad on it at once (unless it was flooded or something). This tells me that the current combination of all diagnostics, parts condemnations, and repairs are likely not accurate.

Here'* where I'd start: I haven't heard that the brake lights staying on ever got repaired. I'd fix that issue first. It is likely the Brake Pedal Position Sensor as described above. It just could be causing all of this.

Are you suggesting i replace the sensor? how do i check this? I never personally checked it bc i assumed one of the 4 mechanics that have looked at it would have chekced it first.

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Boilerplate: Professional driver on a closed course, use as directed, not liable for anything, results may vary, past performance is not indicative of future results, no purchase necessary, optional features shown, use at your own risk, yada, yada, etc.

Nothing wrong with that mileage. I have several that are over 200,000 right now. Usually cheaper to repair than to replace!

So . . . a salt region. How bad is the rust?

Okay, here'* a thing to try:
1. Pull the pedal all the way up.
2. Let go gently
3. Push the pedal down very little, like 1/8" and keep it there
4. Do a brake pedal position sensor relearn
5. Push it a few times
6. Do the brake lights act as they should?
7. Try this for a while.

Here'* the thinking here: The pedal and sensor all have a little wear and things aren't perfect any more. The spring might be a little tired as well. The pedal doesn't always return to the exact same "up" position as reliably as it used to. It might be off by a hair or a smidge, so little that us humans can't really tell. The sensor is really really accurate and sensitive, so when you relearn in one position, and the pedal ends up in a slightly different position on the 327th time you release it, the sensor knows. One alternative would be to rebuild the whole brake pedal assembly, including all bushings and pivots etc. to be like brand new. I don't know if this is possible, and I'm sure it would be expensive. Maybe the entire assembly can be bought new. Both of these are likely to be expensive, if they're possible at all. This alternative "tricks" the Brake Pedal Position Sensor to think that the pedal is "up" while it is very very slightly down.

The downside: If the sensor thinks the pedal is higher than the "up" position that it learned, it will turn the brake lights on for that as well. You can tell it is doing this if the brake lights are stuck on, and pressing the brake pedal down slightly turns them off, and then pressing the pedal down slightly further turns them on again.

The upside: There is a small range where the brake lights will stay off, you just have to find it. You might have to try the process several times, with different heights in Step 3.

Your mechanic friend will know. This is where you can see a waveform of the sensor output to look for irregularities and proper performance.

I'm thinking that it is a wiring issue, and not the wheel speed sensor itself, that is the issue.

Okay, this tells me that something central to the whole braking system is doing this. I can't find documentation on this, but I know some manufacturers started producing cars that would pre-pressurize the brakes in anticipation of a stop. Your car has Brake Assist, which helps apply the brakes aggressively in emergency situations. What I can't find is whether or not it would pre-pressurize. If it does, it would totally make sense that it thinks you are starting to press the brake pedal because the sensor is improperly telling it this. If this is the case, fixing the Brake Pedal Position Sensor might solve all of this.

We can fiddle with this later, after we figure out that we aren't cooking the brakes any more.

Wow, that'* crazy!

Interesting! That could also be all four brakes dragging as well. The engine can over-power the front brakes if they're only dragging a little, but the rears, if they are dragging, would just be dragging, which would be much worse on snow and ice.

Okay, yeah they were due for replacement. Nine years is a pretty good run.

I tend to agree. I've only seen a few bad brake boosters in my life, and only one here on GMForum. They're very reliable, and I've never seen one go bad this way. One way to know for sure would be to plug off the vacuum line to the brake booster and see if the dragging continues. WARNING: The brake pedal would be very "heavy" in this condition and may require both feet on the pedal pushing with the strength of Hercules to get normal braking performance.

I bet this is Electronic Brake Control Module.

"passed and failed" on so many of these is weird. I wonder if these are currently messed up because there have been so many things messed with while this car has been getting diagnosed.

I'm still suggesting to do the Brake Pedal Position Sensor thing up there first.

Sorry to say: This seems to be becoming the typical dealership experience more and more as time goes on. For some reason they don't say "When it'* time to schedule maintenance or you need vehicle repair services, turn to the vehicle care experts at GM Certified Service, unless the problem is slightly more difficult than most issues, in which case we'll 'diagnose' the car for the shortest period of time necessary to clearly understand that we don't know how to fix it, and then we'll guarantee you the opportunity to leave with your car and a hopeless feeling that it can't be fixed by anyone because we claim to know your car better than anyone and even we can't figure it out."

LOL that'* their lawyers talking, or likely a trained response that the lawyers require the phone minions to say in similar situations. I believe a lot of the reason GM even has someone to talk to about these kinds of things is so they have an avenue to mitigate risk.

Agree on the uncommanded hydraulic pressure.

Wow, what a mess!

Here'* the thing though, I don't see a clear diagnosis of a bad module or pump.

This is like the Microsoft diagnosis: Everybody blames Microsoft because they see the problems while they use Windows, but by that logic they can also blame the monitor because it is also there for everything they see. Sometimes it is Microsoft. Most of the time it is not. Almost always it is not the monitor. On your car, the pump and module are there, yes, but do are the pedal and booster and master cylinder and brake lines and pedal sensor and the logic that makes it all go. The dealership os oten the last to understand the interactions of all of these with each other.

I'd be curious what part of the pump they think it is. Motor, valve stuck open or closed, electrical, etc.

The way to check one if to connect to the computer and monitor its movement to see if it consistently can find low, high, and that the reading is consistent in relation to the movement of the sensor or brake pedal. These don't go bad very often. Like I explained above though, everything around them can wear and lead to situations that the engineers don't account for.

With all this stuff going on, and you getting ping-ponged all over creation trying to fix it, I have to look at the whole situation from 30,000 feet. What I see is a bunch of unexplained stuff, lots of guesswork, and a known issue with the brake pedal position sensor. In this kind of situation, I'd default to fixing the issue I know needs to be fixed, and see if anything else gets fixed as a result of that.
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P.*.: I had to split my response into two posts as we had surpassed the 20,000-character limit by 497. I didn't know there was a limit until now, LOL