The ABS discussion thread

[Thad E Ginathom]

Unknown, unbranded component, DIYed into brake system?

Just Say No!

[DerAlte]

Originally Posted by devansn

... Anyone has seen this item on ebay? ...

Originally Posted by Thad E Ginathom

Unknown, unbranded component, DIYed into brake system?

Just Say No!

Their description says "Beyond a certain pressure point, it releases the pressure on the calipers, reducing the pad's grip on the disc in turn, and thus allowing the wheel to turn". The electrical equivalent of that is the MOV in spike busters!

If the pressure is let off beyond a certain point, it is likely that it will reduce the braking effectiveness under normal circumstances as well.

[Sutripta]

Has been marketed as "ABS for Bikes" for sometime now. From what I could make out earlier, deliberately made the brakes spongy. Rationale: so that novices don't lock up the front wheel!

Regards
Sutripta

[AWD]

Don't know whether shared earlier;

http://www.shifting-gears.com/2015/0...ory-from-2017/

[roby.thomas]

Originally Posted by Viju

Hence, even if the ABS motor fails, only the ABS warning lamp will come on and Brake Warning Lamp will not come on (meaning base brakes will continue to function properly). If valve failure occurs, base brake fails.

This is so beautiful to get someone who knows how stuff works and indeed involved in making such things. My interest in the intrinsic working of ABS kicked in only after my car got into this condition (new one, about 3-4 months old).



The problem comes on and off, and is diagnosed to something like Valve Relay Malfunction as per their scan tools, and the part ordered would perhaps take a week or more than that to arrive. I am all set out for a long trip to pursue this weekend. This vehicle has been given back to me to drive around, with the assurance that there is indeed no problem except ABS perhaps wouldn't work. After reading your note, I am like . Does the base braking system not work ? As of now, the vehicle stops precisely like ever before.

[HappyWheels]

Originally Posted by roby.thomas

...The problem comes on and off, and is diagnosed to something like Valve Relay Malfunction as per their scan tools, .. Does the base braking system not work ? As of now, the vehicle stops precisely like ever before.

Have, and still facing, the same issue, but in my Safari. Need to get the sensors replaced.

Your brakes will work perfectly fine but your ABS will not work, meaning, no pulsation (and corresponding benefits) when the wheels lock out.

Drive safe.

[honeybee]

My Accord has developed a brake problem. The pedal suddenly plunges inside when I step on it. The problem isn't consistent, and is intermittent.

I bled all the four brake points to ensure there is no error trapped inside. The brake pads too are in good condition - anyways the brake pedal issue is not much about the brake pads.

The handbrake has always worked fine, so that means the brake problem has to do with the hydraulics.

In hydraulics, the brake oil is clear green, no contamination and all four lines bled so we can eliminate any air trapped inside. The brake oil levels are not reducing so we can also rule out leakage.

So that leaves two parts: The master cylinder and the ABS. I do not know how to check if the master cylinder has gone bad, but since the brakes do seem to work majority of the time, I would leave out the master cylinder failure for the moment. Also this is a part that does not easily go bad.

That leaves us with the ABS. Since a few weeks the ABS light has been lit up on the dashboard, so there is something wrong with it. I had had a rat inside the bonnet before the ABS light issue came up, so I am speculating that the rat chewed off some wires which caused the ABS light to come up (I could see a chewed wire near the front left wheel fender.

After checking online, it does seem that if the ABS malfunctioned, i.e. if the ABS determined that one of the wheels was locked up, it would ease up on braking on that wheel and this could lose the pedal feel. So I would like to eliminate the possibility of the ABS playing foul with my brakes.

I have been driving non-ABS vehicles all my life, and don't see any imminent threat if the ABS is disabled. Replacing the ABS modulator would cost around 50k as per estimate by Honda, and so I would like to eliminate this possibility by disconnecting or disabling the ABS.

How do I disable it? Do I remove the fuse for the ABS? Any wiring to be removed? Has anyone done this before?

[roby.thomas]

I have a question related to ABS module replacement in my car. Post this repair, while on a long trip I observed that the speedometer clocks about 5-10 Km/Hr more than the actual vehicle speed. How do I know this is by comparing with the speed reported by GPS. The GPS and Speedometer agreed each other in my prior car, but I never checked it in this vehicle. So I can't be sure that this is after ABS module replacement. Is there a possibility that the incorrect reading on Speedometer is linked to ABS module replacement ?

I am ok with this defect since, it reports a higher speed while I am actually driving at a lower speed. That's erring on to the safer side.

[::CMS::]

Speedometer and GPS speeds will always be different as the manufacturer has kept the offset for several reasons, however the GPS speed is the accurate speed except the slight +\- or negligible read errors.

[Jeroen]

Originally Posted by ::CMS::

Speedometer and GPS speeds will always be different as the manufacturer has kept the offset for several reasons, however the GPS speed is the accurate speed except the slight +\- or negligible read errors.

to add, GPS speeds are very accurate, but become unreliable during acceleration and braking. So you need to drive at a steady speed for an accurate reading.

Typical GPS speed accuracy can be better then 0.5km/h, depending a little bit on circumstances.

Where on most odometers the in-accuracy is essential a percentage of the reading, on a GPS speed it is an absolute number. So the faster you go the smaller impact it has.

Another anorak fact: GPS speeds go up to 999MPH. You want to go faster than that, you will require a different kind of speed measurements.

Something to do with military specfications from the origins of GPS I believe,

Jeroen

[Mad Max]

Originally Posted by Aroy

. ABS has also convinced drivers that the car will stop faster in any situation, with the result that where as old timers used to monitor the traffic and road condition to assess stopping distance, people are now oblivious to it assuming that ABS will stop the car instantaneously

https://en.wikipedia.org/wiki/Anti-lock_braking_system

The Wiki puts things in a slightly different note. Please go through it.

[JediKnight]

Originally Posted by centaur

Isnt it the contrary? If it increased the distance why would any manufacturer promote it in the first place? We are basically saying that okay so your car stops in X meters without ABS and now with our new revolutionary ABS technology your car will stop in X+Y meters (instead of X-Y meters). Sorry but doesnt make sense to me.

ABS increases braking distance and can reduce control in certain road conditions like rutted /gravelly/mud roads etc.

[Aroy]

Originally Posted by Mad Max

https://en.wikipedia.org/wiki/Anti-lock_braking_system

The Wiki puts things in a slightly different note. Please go through it.

ABS generally offers improved vehicle control and decreases stopping distances on dry and slippery surfaces; however, on loose gravel or snow-covered surfaces, ABS can significantly increase braking distance, although still improving vehicle control.[2][3][4]

We learnt to "Pump" the brakes for better efficiency. More relevant we learnt to drive keeping in mind the total environment around us. Checking the road conditions ahead, anticipating erratic driver behavior. What technology has done is to give us a false sense of safety relying on technology, and ignoring basic safe driving norms.

What I think OP wanted to express is that all the technology has made us forget the basics; thus dumbing us; and relying totally on technology, which if it fails may be disastrous in emergencies.

[studentonwheels]

Originally Posted by centaur

Isnt it the contrary? If it increased the distance why would any manufacturer promote it in the first place? We are basically saying that okay so your car stops in X meters without ABS and now with our new revolutionary ABS technology your car will stop in X+Y meters (instead of X-Y meters). Sorry but doesnt make sense to me.

Actually, ABS works by braking your tires in a release-and-clamp pattern so that your wheels don't lock. Most people who never drove on snow or ice wont know this. It actually feels like your brakes clamp then release, then clamp again. This is done solely to prevent wheels from locking that can send your car into a spin. I've seen that happen a lot here in Iowa on older cars without ABS. Then again, there's always the guy who thinks his car can do it all and rear ends someone. Don't get me wrong, my car has ABS too and I'm indeed grateful for it when we get 6 inches of snow. But I know how it works, so I ensure that I don't abuse it. And I still look either side and over my shoulder when I reverse despite having a backup cam. I guess that's been my point all along:Its great to own a tech loaded car but don't forget the basics.

[MaheshY1]

Originally Posted by studentonwheels

...ABS in fact increases your stopping distance...

That can't be true. Friction stops cars. Skidding on snow with wheels locked means lesser friction.

No matter what the condition, snow, gravel, mud, or sand, ABS will always bring the car back to a stop faster and more importantly, in a straight line.

Shoot me if I'm wrong.

About the tech side, here's a post about self driving cars: https://www.gaadi.com/car-feature-st...f-self-driving