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Old 2nd June 2015, 11:12   #541
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Default re: The ABS discussion thread

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Originally Posted by dhanushs View Post
As long as you don't have a brake malfunctioning light on, you shouldn't have a problem with braking. Only thing is your ABS might not be working. It's safe to drive. However, do check it up as soon as possible.
Agree, please be very cautious if you see the brake malfunctioning light in conjunction with the ABS or on its own.

Intermittent ABS warning light usually means the ABS system is still working. If it comes on permanently there is definitely something wrong with the ABS system and it will be permanently disabled.

The only way to properly check, as I stated before, get it hooked up to an OBS analyzer and check the fault codes. Typically these intermediate faults, do generate a fault code that gets stored.

Jeroen
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Old 2nd June 2015, 14:12   #542
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Default re: The ABS discussion thread

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Originally Posted by dhanushs View Post
As long as you don't have a brake malfunctioning light on, ...
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Originally Posted by Jeroen View Post
Agree, please be very cautious if you see the brake malfunctioning light in conjunction with the ABS or on its own. ...
Which is this "brake malfunctioning light"?

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Originally Posted by blueblooded View Post
... The ABS warning light keeps lighting up momentarily ...
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Originally Posted by Jeroen View Post
... Intermittent ABS warning light usually means the ABS system is still working. ...
Terms like "momentarily", "intermittent" etc. can make things really ambiguous. There is a difference, if one observes carefully, between random flickering (aperiodic, can light up any time, go off then not reappear for a long period in between the next time) and flashing (periodic, has a pattern to it).

ABS light is not expected to flicker randomly - can happen only if there is a dry solder on the LED or resistor associated with the ABS indicator. Otherwise, it is expected to either stay on, go off or convey a fault code by flashing a fixed number of times, then off (repeats). If this happens, the right thing to do is to go to the workshop and use a diagnostic scanner to read the recorded fault(s).

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Old 2nd June 2015, 14:16   #543
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Default re: The ABS discussion thread

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Which is this "brake malfunctioning light"?..
Well, I tried to generalize. Meant: any warning light related to the braking system, and not ABS specific light.
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Old 2nd June 2015, 19:16   #544
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Default re: The ABS discussion thread

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Originally Posted by DerAlte View Post
Which is this "brake malfunctioning light"?

ABS light is not expected to flicker randomly - can happen only if there is a dry solder on the LED or resistor associated with the ABS indicator. Otherwise, it is expected to either stay on, go off or convey a fault code by flashing a fixed number of times, then off (repeats). If this happens, the right thing to do is to go to the workshop and use a diagnostic scanner to read the recorded fault(s).
On cars with ABS there tend to be two warning lights. One, usually amber for the ABS, and one, usually red for the normal braking operation.

ABS tends to be is amber, which tend to be more of a cautionary nature and the 'regular brake' is red, warning nature. When your brake (red) light comes on, you really ought to stop and investigate immediately. The ABS (amber) is an indication that the ABS might not be working properly, but the normal braking system should still work.

I've heard about some ABS lights showing up for for instance low level fluid in the master brake reservoir, which really ought to throw a brake warning light in my opinion. I'm not sure to what extent these warning light, colours and what they all mean are really universal?

If the internet is to be believed (and my limited experience) ABS flickering (i.e. random on off) is something that happens a lot.

Jeroen
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Old 2nd June 2015, 21:17   #545
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Default re: The ABS discussion thread

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Originally Posted by Jeroen View Post
......ABS flickering (i.e. random on off) is something that happens a lot.

Jeroen
Personal experience on our Figo Titanium, something as mundane as dust can cause a flickering ABS warning. Doesn't even necessarily mean an ABS malfunction, just the ECU conned into thinking so. A quick inspection/cleaning of the sensors at A.S.S. and everything is usually back to normal. Never had a 'real' issue with ABS in 5 years of ownership so far, despite several instances of 'flickering' ABS warning lamp.

Last edited by Chetan_Rao : 2nd June 2015 at 21:18.
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Old 2nd June 2015, 21:25   #546
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Default re: The ABS discussion thread

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Originally Posted by Chetan_Rao View Post
Personal experience on our Figo Titanium, something as mundane as dust can cause a flickering ABS warning. Doesn't even necessarily mean an ABS malfunction, just the ECU conned into thinking so. A quick inspection/cleaning of the sensors at A.S.S. and everything is usually back to normal. Never had a 'real' issue with ABS in 5 years of ownership so far, despite several instances of 'flickering' ABS warning lamp.
Well, I concur flickering happens, but it should be investigated I think. That's why you need to hook it up to an OBD analyser, preferably a manufacturer specific one. Generic readers don't provide much info on ABS systems.

I would not feel comfortable if any warning or caution light would flicker. It flickers for a reason and you wouldn't want that to happen when you are making an emergency stop.

How do you know your ABS is working properly? Do you test it every time after it flickers? Or do you assume it works fine, when the flickering stops?

Jeroen
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Old 2nd June 2015, 21:36   #547
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Default re: The ABS discussion thread

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Originally Posted by Jeroen View Post
Well, I concur flickering happens, but it should be investigated I think. That's why you need to hook it up to an OBD analyser, preferably a manufacturer specific one. Generic readers don't provide much info on ABS systems.

I would not feel comfortable if any warning or caution light would flicker. It flickers for a reason and you wouldn't want that to happen when you are making an emergency stop.

How do you know your ABS is working properly? Do you test it every time after it flickers? Or do you assume it works fine, when the flickering stops?

Jeroen
My family has an automotive lineage (grand-dad had a garage) so we're careful bordering on paranoia with our cars, so no assuming anything.

My parents live in an area prone to dust, so we have the occasional flicker every few months (not sure if there's a direct correlation, but our Ford A.S.S. believe so). The A.S.S. is in the same neighborhood so we drop in for a quick check whenever it happens but from all instances I remember (we've probably had about 6/7 of those in 5 years), nothing more than sensor inspection/cleaning was ever done on our car. I cross-checked with another A.S.S. just to be sure mine's not shrugging off an underlying problem, but they said the same. No faults/errors on the OBD device they use either, which I verified.

I did test it a few times myself when this happened (we have plenty of open space with good vacant roads around our home), and ABS functioned normally every time I tried (pulsating pedal on hard braking, no skidding and able to maneuver the vehicle until it stopped).

Is there something I or the A.S.S. folks are missing?

Last edited by Chetan_Rao : 2nd June 2015 at 21:40.
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Old 2nd June 2015, 21:53   #548
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Default re: The ABS discussion thread

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Originally Posted by Chetan_Rao View Post
Is there something I or the A.S.S. folks are missing?
You should not get a flickering ABS light that often. It does happen, but what I read from your posts, it happens fairly regularly. something must be wrong and I doubt very much dust is the problem.

Did you use a generic code reader or a manufacturer specific one?

Generic code readers are not that useful on diagnosing ABS. I would think if there is a flickering ABS light it would throw a code.

Jeroen

Last edited by Jeroen : 2nd June 2015 at 21:55.
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Old 2nd June 2015, 22:06   #549
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Default re: The ABS discussion thread

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Originally Posted by Jeroen View Post
You should not get a flickering ABS light that often. It does happen, but what I read from your posts, it happens fairly regularly. something must be wrong and I doubt very much dust is the problem.

Did you use a generic code reader or a manufacturer specific one?

Generic code readers are not that useful on diagnosing ABS. I would think if there is a flickering ABS light it would throw a code.

Jeroen
I can't recall the brand of device the A.S.S. use off the top of my head, but I do remember it was the same at both the places I've taken the car to, so I believe it's a manufacturer-specified device. How can I tell if it's suitable for ABS diagnostics, or rather which one should I be using?

If there's reason to believe Ford's diagnostics is ill-suited to what they're looking to diagnose, I may have to resort to an independent evaluation (if I can find someone with the proper equipment or procure one myself if viable).

The car has been with Dad in another town for the last year or so, and I don't recall him mentioning an ABS warning in that period. Not sure if that (dis)proves anything.

The ABS has always behaved as intended when I tested it on-road and Ford A.S.S. concurs nothing's wrong, so I'm at a loss for ideas on what to do next.

Last edited by Chetan_Rao : 2nd June 2015 at 22:09.
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Old 3rd June 2015, 08:46   #550
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Default re: The ABS discussion thread

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Originally Posted by Chetan_Rao View Post
The ABS has always behaved as intended when I tested it on-road and Ford A.S.S. concurs nothing's wrong, so I'm at a loss for ideas on what to do next.

Have a look at this:

http://www.obd-codes.com/trouble_codes/

If you check the generic codes you will find some codes that are related to the brake system, but I dont think there are any related to ABS.

So if you hook up a generic code reader (OBD-analyzer) to a car, you wont find any error codes for ABS. So the ABS could be wonky but you'd never be able to tell from the generic code reader.

You need to have a reader that can read specific manufacturer codes, that means codes starting with P1xxx. You might want to check with the manufacturer data first what type of ABS codes they actually have implemented.

I have no immediate answer to what is happening with your car. Other then what has been stated before. ABS light should as a rule not flicker randomly. If it does, something is amiss. I dont believe dust can be the culprit. In my experience it is usually something like a bad connector, poor ground, problem in the wiring etc.

On the up side, as long as the ABS light doesnt come on permanently your ABS system is actually working ok. All intermittent problems can be a real PITA to troubleshoot.

Good luck

Jeroen
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Old 3rd June 2015, 08:57   #551
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Default re: The ABS discussion thread

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Originally Posted by Jeroen View Post
Have a look at this:

http://www.obd-codes.com/trouble_codes/

If you check the generic codes you will find some codes that are related to the brake system, but I dont think there are any related to ABS.

So if you hook up a generic code reader (OBD-analyzer) to a car, you wont find any error codes for ABS. So the ABS could be wonky but you'd never be able to tell from the generic code reader.

You need to have a reader that can read specific manufacturer codes, that means codes starting with P1xxx. You might want to check with the manufacturer data first what type of ABS codes they actually have implemented.
ABS malfunction codes generally start with Cxxx (C for Chassis). Actual codes vary from manufacturer to manufacturer. P codes I believe are only for Powertrain.

This is the link to the chassis related codes on the same site.

http://www.obd-codes.com/trouble_cod...ssis-codes.php

Cheers
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Old 3rd June 2015, 14:30   #552
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Default re: The ABS discussion thread

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Originally Posted by Jeroen View Post
Have a look at this:

http://www.obd-codes.com/trouble_codes/

........it is usually something like a bad connector, poor ground, problem in the wiring etc....

I guess a full ABS inspection is in order at the next service. I'll put that on our service checklist.

Thanks for the link and advice.
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Old 3rd June 2015, 16:10   #553
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Default re: The ABS discussion thread

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Originally Posted by Jeroen View Post
On cars with ABS there tend to be two warning lights. One, usually amber for the ABS, and one, usually red for the normal braking operation. ...
Not able to relate to the red for normal braking operation that you are referring to. Usually there are 2 distinct red indicators - Parking Brake On (Handbrake; P in a circle in parenthesis), and Brake Oil Level Low (exclamation mark in a circle in parenthesis).

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... ABS tends to be is amber, which tend to be more of a cautionary nature and the 'regular brake' is red, warning nature. ...
ABS indicator *has* to be, not merely 'tends to be', amber - the letters ABS in a circle in parenthesis. This lamp is controlled by the ECU, so there is no (random) flickering to be expected because the ECU sets the lamp to a definite state.
* Goes on in health check phase, goes off thereafter in a healthy system.
* If it stays on, it means there is trouble in the ABS system.
This usually signifies loose contacts or open circuit in sensor wiring, insufficient signal, erratic / intermittent sensor signals, implausible signals, etc. Diagnostic queries to the ABS ECU reveal the actual reason. Dust on the reluctance sensors doesn't trigger anything, unless it is iron dust which confuses the sensor. Dust usually affects the connection of the sensor to the harness wires, causing intermittent loose contact in extreme cases. The wheel sensor is a hermetically sealed contact-less reluctance sensor.
* If it goes on and then off during braking, it means ABS acted in that period (in case someone didn't notice the pedal juddering)
* If it flashes (flashes a definite number of times and then pauses (dark) before repeating the flashes), it is trying to convey an ABS diagnostic code

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Originally Posted by Jeroen View Post
... When your brake (red) light comes on, you really ought to stop and investigate immediately. ...
AFAIK the brake light comes on only in the tail lamp - there is no lamp in the instrument cluster which lights up whenever brakes are pressed. Would be an irritating feature if it exists - wouldn't convey anything other than what the driver is doing with his right foot, and is already aware of

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... I've heard about some ABS lights showing up for for instance low level fluid in the master brake reservoir, which really ought to throw a brake warning light in my opinion. ...
You are absolutely right in expecting that. The Low Brake Fluid Level indicator predates ABS by decades, and was never hijacked by the ABS system. It is always external to the ABS system. Whoever said that (doesn't matter how many did), made an erroneous uninformed observation.

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... I'm not sure to what extent these warning light, colours and what they all mean are really universal? ...
The colors and significance are standard and universal.

* Amber stands for warnings / errors that do not directly affect the functionality of the equipment
* Red stands for errors that affect the equipment functionality.

Equipment in this context is the automobile, not the subsystem like ABS. Low Brake Oil will make the brake system, and hence the car, dysfunctional.

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Originally Posted by Jeroen View Post
... If the internet is to be believed (and my limited experience) ABS flickering (i.e. random on off) is something that happens a lot. ...
Internet also says a lot of other things which are grossly untrue and defy logic. If you believe the internet, UFOs definitely exist (except one can't figure out why ONLY over US)
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Old 5th June 2015, 08:56   #554
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Default re: The ABS discussion thread

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Originally Posted by DerAlte View Post
Not able to relate to the red for normal braking operation that you are referring to. Usually there are 2 distinct red indicators - Parking Brake On (Handbrake; P in a circle in parenthesis), and Brake Oil Level Low (exclamation mark in a circle in parenthesis).
On many (European version) cars I'm famililar with it is one combined red warning light that combines parking brake and low level brake fluid

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Originally Posted by DerAlte View Post
AFAIK the brake light comes on only in the tail lamp - there is no lamp in the instrument cluster which lights up whenever brakes are pressed. Would be an irritating feature if it exists - wouldn't convey anything other than what the driver is doing with his right foot, and is already aware of
My bad, I meant brake warning light.

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Originally Posted by DerAlte View Post
The colors and significance are standard and universal.

* Amber stands for warnings / errors that do not directly affect the functionality of the equipment
* Red stands for errors that affect the equipment functionality.

Equipment in this context is the automobile, not the subsystem like ABS. Low Brake Oil will make the brake system, and hence the car, dysfunctional.
Thanks, I'm not hundred percent sure if the meaning of a particular light is always the same. e.g. see my observation above on 2 versus 1 brake warning light


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Originally Posted by DerAlte View Post
Internet also says a lot of other things which are grossly untrue and defy logic. If you believe the internet, UFOs definitely exist (except one can't figure out why ONLY over US)
You know I have said it a billion/zillion times on this forum already. Dont believe the internet. To be fair, the internet occasionally does get it right. The trick is to figure out when!

Jeroen
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Old 10th August 2015, 22:41   #555
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Default re: The ABS discussion thread

Hello everyone,
I have a 2013 Ford Ecosport (ABS equipped). I tried checking to see if the ABS works a couple of days back. While driving ( in an empty lot) at 20-30 kmph I slammed the brakes while turning the steering wheel, both the front wheels locked up and the car skidded straight instead of turning . That's not supposed to happen right? The wheels shouldn't lock up and the car should turn where I want it to. I complained to the service manager during the service and he told me that the ABS only works when the car is doing speeds above 50 km/h. Is that true?
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