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Old 26th May 2011, 16:53   #16
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Default re: My Safari ABS does not engage?

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Originally Posted by dadu View Post
...I checked with Bosch(who is the ONLY ABS manufacturer in India)...
True. My Safari's ABS is made by Bosch and I do feel pulsation on the brake pedal when it is activated (usually during panic braking situation). The (ABS) light comes on briefly when I switch the ignition to "on" position- it stays there for few seconds (does self-check routine) and then goes off.

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Originally Posted by akmits_bhp View Post
Any other Safari 4x4 owners experienced it?
Safari ABS does work. I think thread title is somewhat misleading. It may be that your unit has a problem. Title should be changed to something like "My Safari ABS does not engage".

-BJ
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Old 26th May 2011, 21:01   #17
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Default re: My Safari ABS does not engage?

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Originally Posted by akmits_bhp View Post
... I recently had the experience of applying hard-brakes ... I felt the wheels locked and I did not hear the typical ABS sound/vibration from the wheels. The ABS-diagnostics light does come up and goes off when I switch ON the SUV. ...
You must be actually a good driver, and must have braked on time and quite decently - which did not require the ABS to act. However, you must have done this analysis afterwards, and as someone said here, under the panic conditions you may not have observed the events correctly, especially if your expectancy was something else ('the typical ABS sound/vibration from the wheels').

ABS does not produce any sound or vibrations at the wheels, one only feels the pulsations through the brake pedal. The ABS diagnostics / error light in the dash is just that - it indicates either 'diagnostics active' or 'error occurred'.

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Originally Posted by AVR View Post
The tyre skid marks on an ABS-enabled car under hard braking are not 2 continuous black lines but two dashed/broken black lines ...
Not! A car with working ABS will not produce *any* skid marks, dashed, dotted or continuous, for the time that ABS acted. Someone who can 'modulate' brakes skilfully *in a car without ABS* under controlled conditions (not panic conditions in traffic, when they would be busy saving the car) could just perhaps make a dashed skid mark line.

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Originally Posted by dadu View Post
... Bosch(who is the ONLY ABS manufacturer in India), ...
No they aren't! Not sure if the others have managed to sell to the ultra-cost-conscious Indian car manufacturers, though.
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Old 26th May 2011, 23:41   #18
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Default re: My Safari ABS does not engage?

Thanks guys.

I agree the title should be "My Safari ABS does not engage?" Mods please change the title if you think it is needed.

I will try the brake test myself before taking it to TASC. But, I am pretty sure ABS did not engage that day. I also have some experience with ABS and can make out when it engages.

Thanks again
-a
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Old 26th May 2011, 23:52   #19
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Default re: My Safari ABS does not engage?

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Originally Posted by DerAlte View Post
Not! A car with working ABS will not produce *any* skid marks, dashed, dotted or continuous, for the time that ABS acted. Someone who can 'modulate' brakes skilfully *in a car without ABS* under controlled conditions (not panic conditions in traffic, when they would be busy saving the car) could just perhaps make a dashed skid mark line.

No they aren't! Not sure if the others have managed to sell to the ultra-cost-conscious Indian car manufacturers, though.
ABS-systems can result in skid marks.

Surely not dotted/ribbed but dashed skid marks do show up in ABS-enabled cars also. When brakes lock and release the tyres there is this alternating between tyre trying to skid because tyres are locking and when they are released and felt through the pulsating feeling on the brake pedal. The same pulsation also gets transferred to the tyre and manifests itself through the dashed skid marks.


ABS & skidmarks - Honda-Tech Post no: 22 might help.
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Old 27th May 2011, 00:33   #20
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Default re: My Safari ABS does not engage?

Sir, please read and understand the actual information source - TARorigin - which is the link at the start of Post #22. A 'skid' mark (produced by the same patch of tyre rubber over a distance) is not the same as a 'scuff' mark (contact impression left by a series of patches around the tyre). If one looks carefully, under some conditions hard acceleration also produces 'scuff' marks like ABS - and they are not called 'skid' marks.
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Old 27th May 2011, 11:27   #21
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Default Re: My Safari ABS does not engage?

Quote:
Originally Posted by DerAlte View Post
Sir, please read and understand the actual information source - TARorigin - which is the link at the start of Post #22. A 'skid' mark (produced by the same patch of tyre rubber over a distance) is not the same as a 'scuff' mark (contact impression left by a series of patches around the tyre). If one looks carefully, under some conditions hard acceleration also produces 'scuff' marks like ABS - and they are not called 'skid' marks.
Yes. Probably calling them skid marks was an error on my part. Am still not sure. I have noticed these dashed tyre marks (to be safe ) on many expressways in the US and that's the reason for my view. Having seen them quite too often led me to believe that it could be ABS and not an expert driver everytime. Apart from that the dashed tyre marks is probably where you and I have the same opinion as the lock-unlock-lock-unlock action of the brakes would result in multiple portions of the tyre face meeting the road.
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Old 27th May 2011, 16:16   #22
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Default Re: My Safari ABS does not engage?

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Originally Posted by dadu View Post
You are right, I checked with Bosch(who is the ONLY ABS manufacturer in India), the light glows only under malfunction. (I thought I had read light on activation, I was wrong)

The only way to detect ABS in Action is the pulsating brake pedal and continuous clicking noise.
Continental also manufactures ABS in India.
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Old 27th May 2011, 16:36   #23
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Default Re: My Safari ABS does not engage?

Last weekend, I was in Hyderabad and was driving behind a trailer truck. This was near Miyapur. This road has a lot of junctions while also allowing the traffic to reach good speeds in-between. At one such junction the trailer slowed down and I suddenly saw a white puff of smoke. I was surprised since there wasnt any three wheeler any where nearby. Then I observed that the trailer's rear wheels were locking just for an instant before ABS kicked in and the resultant skid was the cause of the white smoke. This was due to a loaded trailer, sudden braking and the higher speed.

Such a situation will definitely lead to the broken black lines, wont it? I am basing this deduction on the assumption that ABS is a legal requirement for the tractor-trailer trucks for the last few years.
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