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14

tl;dr: No. This sort of vehicle dynamics question best addressed by Racing Car Vehicle Dynamics What follows is a basic discussion at the high school physics level. As you will see from the reference text, high school physics is insufficient to statically model the complete vehicle system. A dynamic model is required to agree with easily obtainable ...


11

Normal Sounds The sound you are hearing is the ABS releasing pressure within the system to allow the wheels to continue to rotate and not lock up when you apply the brakes in low friction conditions. As the snow builds up and you encounter low friction driving conditions due to snow and ice the ABS will kick in more frequently because you are encountering ...


6

Turns out that there was a big pocket of air in the system. Sucking it out made everything return back to normal, thankfully. I also tried to replicate what happened in the first place by driving on some ice and getting the tires to lock up and activate the ABS. I did it a bunch of times and nothing bad happened. So hopefully it is fixed.


6

Sounds to me like the technician didn't burnish (or seat) the brake pads. Anytime you replace the brakes pads you should make several hard stops (not enough to activate the ABS) from 35 and then 55 mph. This seats the pads to the rotors, and eliminates the spongy feeling.


6

Yes, just get all the parts from an APV that has ABS. You will likely need: all 4 wheel hubs because the sensor is built in the wiring the ABS controller You may need to swap your ECU for one that knows about ABS controllers.


5

ABS (should) allow for the best stopping traction you can get (in a perfect world) on the road surface regardless of road conditions. That said, you see some caveats in the mix there. I'll try to explain. I say should allow for the best. All ABS systems are not created equal. Some work better than others (though I'm not going to break those out). ABS ...


5

If you can get all 4 to lock at the same time then systems that detect differences between wheels won't activate. The system would have to be smart enough to detect exceptionally fast stopping of the wheels in order to work in that circumstance. My MR2 and Eclipse are definitely not that smart. Both are very capable of locking all 4 at the same time and ...


5

General Motors is well known for ABS problems. The problem comes from the speed sensors in the wheel bearings. The sensor slips into the wheel bearing and reads a toothed wheel inside. These sensors are very senesitive to the distance between the end of the sensor and the toothed wheel. When the gap gets too big the sensor can't properly read the toothed ...


5

To my knowledge, access to the ABS module will not be possible through a generic OBDII adapter. The most commonly available option for VW's of this era is a VAG-COM cable with RossTech software on a laptop.


5

Is the car on the floor? Many vehicles, I'm not sure if yours does for certain, feature a brake bias apportioning valve which is essentially a "tap" which opens or closes depending on the position of the rear beam axle. If the car is heavily loaded (i.e. has people in the rear seats and a boot / trunk full of cargo), more braking force is sent to the rear ...


5

I have not been able to find a parts diagram for your model (likely because of the region I live in), so I will explain how to tell which cable is which. If you trace it back, one will attach to the chassis for a ground. That is the negative battery cable (I would check the one with the two small flanges first). The thicker one, with the "L" shaped ...


4

The newer the car the better ABS tends to be, but you can lock up even the best ones if you try hard. On sheet ice it is safer to disable your ABS entirely unless you have a system which is designed for these conditions. After seeing a bad crash where a long slide into a collision was caused by ABS not allowing any grip, I remove the fuse for ABS each ...


4

A problem with the anti-lock braking system will not have caused the issue you are describing. What you are describing can be attributed to about one of two things (or a combination of the two): Driver inexperience in a rear-wheel drive vehicle. Since the vehicle is rear-wheel drive, it will want to kick out faster than a front wheel drive vehicle will. ...


4

Seems like a bad brake caliper piston. When they start to go bad they tend to "stick". Sticking means that the piston inside the caliper is not freely sliding in and out when pressing against the brake pads. The sound you hear could be the caliper freeing itself from the stuck position. The springs sound could also be related because your car uses metal ...


4

It appears that as soon as the vehicle detects a wheel has locked up, the ABS goes into failure mode. This would suggest to me that you may have a fault in the abs module. If it was a wheel bearing or sensor that was at fault, I would expect occasional false activation of the ABS and also normal activation where the pedal judders. It looks instead like ...


4

The ABS light is an indicator of an error caught by the ECU. It usually is an error for a defective ABS sensor or a related brake issue. It's difficult to tell what exactly it is without reading the error code. Some specific problem might be fixed by reprogramming the ABS module, others won't. Depends on the issue and the year of your 528i. Once you get the ...


4

If the sensor itself is damaged it would be a challenging task (if not impossible) to repair it. There could be also other causes. I would suggest you to check the following things: Most of times just the abs ring needs to get cleaned. The ring is on the backside of the wheel hub. Remove the brake disc, then clean the abs ring gently with a wooden spike, a ...


4

What you're describing sounds like the pulsing feedback that the ABS (antilock braking system) provides when it actuates on a slippery surfaces. The best way that I can describe it is as a roughness or rumble in the brake pedal, usually it is accompanied by a matching (for lack of a better word) sound. There may also be a annunciator light in the instrument ...


4

From my personal experience, I can come up with only two cases when ABS is more dangerous than "no ABS": Malfunctioning ABS that kicks in when not required. Some time ago I had a problem with ABS sensor due to which ABS occasionally engaged even on dry surface when it was not supposed to engage. The braking distance increased ~5x to what it used to be. As a ...


3

To answer these questions: Is there any substance to these scientific sounding claims? Yes there is and there is not, these kits simply reduce the total pressure applied onto the brakes by the user and are exactly not "ABS" or Anti-Lock Brakes. Is there any supporting evidence proving/debunking the above? I cannot Give hard evidence but these rudimentary ...


3

You are right to assume that error codes 41/42 are due to a lack of signal coming from the rear right wheel speed sensor. I recently had to address a couple of bad ones on my E39 BMW; the signal wire(s) may be brittle or cut so that signal transmission is no longer possible. I wouldn't worry too much about error code 95 at this point in time. The CAN bus is ...


3

It could be noted that the heads of the sensors get stuck with metal flakes from the brakes wearing down. That has caused a few BMW's we have had through my shop to throw those codes, we cleaned the sensor first and reset the codes as an option for customers. Its an option if you can't get the sensors in a timely fashion.


3

VSC stands for Vehicle Stability Control. It's the part which works in conjunction with the ABS to keep your vehicle stable during a bad braking situation. It also will help you in corners and such which might be a little too much for your vehicle. You decide whether it's important to you or not.


3

It sounds it could be one of two things: Easier fix - PIT-5171 - Debris is preventing the speed sensors from reporting correctly. To diagnose this problem, remove the fuse for the ABS/TCS system and see if the problem persists. If that eliminates the problem, reconnect the fuse and clean the speed sensors with a toothbrush and an electronics cleaner. ...


3

It could also be a defective strut or shock absorber. I am having the exact same issue myself presently. When a strut is empty of fluid and gas there is no dampening effect and you are bouncing on your springs. This effect is also noticed when braking at low speeds as well as when turning. When braking with dead struts your tires have intermittent contact ...


3

First thing to do is a diagnostic scan and find out why the car has turned on it's ABS light. This may give you guidance on the fault. Also, worth having the fault codes cleared and take the car for a test drive. It may be that the fault doesn't re-occur or that it reports a different fault after being cleared. Chances are, if the brakes look visually ...


3

To the second question: How can I figure out if the TSB applies? If it does apply, how can I find out for myself if the reprogramming has been done or not? Apart from experiencing the fault described by the TSB and assuming that is the cause, you cannot unfortunately. More guess work- if you know the dealership which the previous owner used, they may ...


3

That particular sensor doesn't check ABS codes. ABS errors are frequently on a different circuit entirely than check engine codes, and that particular device is only checking engine codes. If you want a complete description of what your tester covers, try this manual.


3

Check out this manual. I don't think your battery is lithium; it's most likely a sealed lead acid battery (SLA, sometimes referred to as AGM, or absorbent glass mat). They tend to be a lot smaller than regular car batteries in terms of dimensions (I have some that are about 3"x4"x5") but are much heavier than lithium batteries would be. https://onedrive....


3

You have to pull (really hard) on this grey lever. It comes out about 3 inches vertically and unlocks the connector:


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