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Old 20th March 2014, 14:52   #1
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Default Strange loss of braking ability. What happened?

Early this week, I was travelling on Mysore Bangalore highway at speeds between 90 & 100. Somewhere after Kengeri, at a break in the median, I noticed a Mahindra Maxx ready to make a U turn from opposite side. There were only left & right lanes on one side and I was on the right lane. There were few two wheelers in the left lane and hence I decided to slow down in my lane and either let Maxx go ahead with the turn or move along if Maxx decides to wait. There was sufficient distance to slow down comfortably and I braked.

The car started slowing down and after about 40% into braking, I felt the braking effect is gone. The brake felt like rubber, it had no effect. For a moment I felt I will overrun the junction and hit Maxx in case he makes the turn.

Finally the car slowed down and came to a stop about 15 feet more than I intended but before the junction. Being early morning traffic was less. Luckily there was no vehicle in front, otherwise I would have hit since I overshot.

After feeling glad that nothing untoward happened, I came out to check the road & tyres. While braking I felt as if the wheels had come off, since there was no braking & steering response. Everything was intact. I started the car and the brakes were fine. I proceeded and rest of the journey was without any incident, though I drove between 60 & 70.

I couldn't figure out what had happened & why the brakes failed. Was it worn out pads? Did I slam the brakes more than necessary? Was this case of brakes locking? Or anything else? I searched on the site & online and but not relate to any incident. It is a till a mystery.

PS: I drive 2006 City, which isn't known for its brakes. But the 185/65/R14 Yokohama C drives improves braking.

Last edited by GTO : 21st March 2014 at 13:47. Reason: Typos
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Old 20th March 2014, 14:55   #2
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Get the lines bled.
If the tires had locked, you'd hear screeching and would see black tire marks on the road.
It's good that you're safe. Just get the braking system checked.
All the pads/disks/fluid/lines.
Do keep us updated.
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Old 20th March 2014, 15:13   #3
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Default re: Strange loss of braking ability. What happened?

Quote:
Originally Posted by H_Dogg72 View Post
Get the lines bled.
If the tires had locked, you'd hear screeching and would see black tire marks on the road.
It's good that you're safe. Just get the braking system checked.
All the pads/disks/fluid/lines.
Do keep us updated.
Also get the brake pads checked. If you were using the brakes consistently & frequently, they might have become hot and lost their ability. But that surely sounds scary. Get a full brake overhaul done and fill the circuit with new brake fluid. Also, do get the master cylinder checked for any leakages.

I will also suggest a brake booster check and changing the vacuum pipe connecting the brake booster to the engine. It is possible that the pipe has a small leakage which let off the pressure while holding up the pedal for long or the valve inside the pipe may have jammed and hence the brakes malfunctioned.

Last edited by saket77 : 20th March 2014 at 15:16.
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Old 20th March 2014, 16:44   #4
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I forgot to ask, were there any warning lights on the dash ?
If the vacuum is finished, it just might show the handbrake light.
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Old 20th March 2014, 16:55   #5
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Default re: Strange loss of braking ability. What happened?

Personally, I would recommend engine braking. It's a great method to slow down and it even helps prevent premature brake-pad wear.

Good to know that you came out of it alright.

Just this morning I'd watched this scary video of accidents at traffic junctions and cross-roads. Sends shivers down my spine just thinking about it!
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Old 20th March 2014, 17:07   #6
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Default re: Strange loss of braking ability. What happened?

How many passengers were there with you? Was there extra luggage too? Extra passengers and luggage can significantly alter the braking characteristics of the car. You have step on the brake pedal a bit harder than what you would if you were travelling alone.

Since everything was OK after that, I suspect that nothing is really wrong with your car. And also, you did stop before the median. It's just that the car didn't stop where you expected it to.

But do take your car to the service center and get the entire braking system checked (just in case).
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Old 20th March 2014, 17:30   #7
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Default re: Strange loss of braking ability. What happened?

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Originally Posted by suhaas307 View Post
Personally, I would recommend engine braking. It's a great method to slow down and it even helps prevent premature brake-pad wear.
Scary indeed. In such cases its better to pump the brake once or twice. Also get the brake pads and disks checked, if the front disks have become thin they will over heat and the brakes will lose traction.

I also prefer engine braking when down hill or emergencies but not for regular use. It will put undue stress on engine and what would you want to replace often Engine or brake pads?
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Old 20th March 2014, 17:33   #8
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Default re: Strange loss of braking ability. What happened?

msdivy, Did you feel loss of steering control when you braked hard? If yes, i'd blame it on Non ABS brakes of your car. Non ABS brakes require certain amount of modulation to avoid locking up the wheels that result in loss of steering control.

Apart from the pedal feel, there are a lot of factors like inadequate pressure on brake pedal, load in the car, condition of tires, tire pressure, road surface etc which decide the actual stopping distance. At speed our perception of stopping distance is also to be blamed, at times of high speed driving, we may be judging the stopping distance to be lower than it actually is.

In an ABS equipped car, the safest approach is to press the brake pedal as hard as possible and let the electronics take over to ensure lock free braking, since the steering control is retained you also have the option to steer away to avoid the obstacle if the collision looks eminent.
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Old 20th March 2014, 17:44   #9
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Default re: Strange loss of braking ability. What happened?

Correct me if I am wrong. But engine braking does not put undue stress on the engine. Infact it is the most recommended practice in situations where you dont actually need a quick deceleration, but just some reduction in speed if you anticipated the obstacle well in advance.

Coming to the situation above, the rubbery effect is felt when the brake assist no longer works. You can replciate this effect. Just switch off your engine at a slight incline at your home or some safe place. If you are only holding on to the foot brakes without the hand brakes, after some time, you will feel as if some stone has been placed under the brake pedal and you will feel that you need to use excessive force just to feel the bite. The new gen swifts (Non Z versions) sometimes have this problem in peak traffic sitations where the brake is unable to deliver the required bite in stop-go braking.

Please show the car to your regular garage. They should be able to sort it out.
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Old 20th March 2014, 18:00   #10
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Default re: Strange loss of braking ability. What happened?

Quote:
Originally Posted by H_Dogg72 View Post
Get the lines bled.
If the tires had locked, you'd hear screeching and would see black tire marks on the road.
It's good that you're safe. Just get the braking system checked.
All the pads/disks/fluid/lines.
Do keep us updated.
I take office bus and I haven't used the car since reaching home that day. I have booked an appointment this Saturday. Sure will get it checked. I didn't hear any screeching sound. But there were black marks at about 30ft from where I came to halt. None after that.
Quote:
Originally Posted by saket77 View Post
Also get the brake pads checked. If you were using the brakes consistently & frequently, they might have become hot and lost their ability.
Could be. I was in bit hurry to make sure my daughter reaches school in time. Hence could have used the brakes more often than earlier times. But didn't feel that was excessive.
Quote:
Originally Posted by H_Dogg72 View Post
I forgot to ask, were there any warning lights on the dash ?
If the vacuum is finished, it just might show the handbrake light.
No warning lights.
Quote:
Originally Posted by smartcat View Post
How many passengers were there with you? Was there extra luggage too? Extra passengers and luggage can significantly alter the braking characteristics of the car. You have step on the brake pedal a bit harder than what you would if you were travelling alone.
Just me, wife & kid. Yes boot was full.
Quote:
Since everything was OK after that, I suspect that nothing is really wrong with your car. And also, you did stop before the median. It's just that the car didn't stop where you expected it to.
When I hit the brakes the car slowed down but midway the braking intensity dropped. That was scary part.
Quote:
Originally Posted by suhaas307 View Post
Just this morning I'd watched this scary video of accidents at traffic junctions and cross-roads. Sends shivers down my spine just thinking about it!
I saw those videos too. If anything had happened, I would have registered case as brake fail. That's common reason given in accidents. I hope ABS helps in these cases.
Quote:
Originally Posted by tazmaan View Post
Scary indeed. In such cases its better to pump the brake once or twice.
Yes, I have heard that advice on this forum but taking my leg off the brake would be last thing I would have done at that moment.
Quote:
Originally Posted by .anshuman View Post
msdivy, Did you feel loss of steering control when you braked hard? If yes, i'd blame it on Non ABS brakes of your car.
I felt loss of steering control along braking control. Thats why when I stopped first thing I did was to check if wheels are in place.
Quote:
Originally Posted by narendra.vw View Post
Did you check the road condition on the spot where you lost the control of your car? I strongly suspect road being slippery. Could have been something like rotten vegetables or oil that had leaked from another vehicle, on the road.
Yes, I checked the road. It was dry. There was some gravel but nothing to be concerned.

Last edited by msdivy : 20th March 2014 at 18:13.
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Old 20th March 2014, 18:07   #11
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Default re: Strange loss of braking ability. What happened?

Quote:
Originally Posted by msdivy View Post


While braking I felt as if the wheels had come off, since there was no braking & steering response.
Did you check the road condition on the spot where you lost the control of your car? I strongly suspect road being slippery. Could have been something like rotten vegetables or oil that had leaked from another vehicle, on the road.
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Old 20th March 2014, 18:16   #12
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Default re: Strange loss of braking ability. What happened?

Quote:
Originally Posted by racer_ash View Post
Correct me if I am wrong. But engine braking does not put undue stress on the engine. Infact it is the most recommended practice in situations where you dont actually need a quick deceleration, but just some reduction in speed if you anticipated the obstacle well in advance.
Absolutely correct. You can do engine braking only when you anticipate a slow down.

Say when you are approaching a speed breaker that you knew was there or a traffic light. Rather than braking, just go down the gears gradually. Don't do engine braking from 5th gear 60kmph to 2nd gear. That will put undue stress and will wear out the clutch.

Emergency braking is all anchors down by standing on the brakes. You cannot do engine braking if your right foot is on the brakes unless you heal and toe to rev match. Not in the league of us regular drivers.
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Old 20th March 2014, 18:20   #13
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Default re: Strange loss of braking ability. What happened?

Oh I have gone through this a lot of times. This happened to you because while hitting the brakes you constantly kept your foot on the brake pedal and did not even for a moment let it 'go' for it to breath. That's why the brakes went numb and in that condition even if you would have stood on the brakes, it would have taken its own sweet long time to slow down. This happened because the brakes got heated.

Last this happened to me was when my brake pads and discs were 3 thousand km old and I had to brake from 140 into a signal which had no one except my car. Since my pads and discs were new and I had a good opportunity to wear them in ( I had never broken them in or braked hard till now after getting them new ) I decided to use this opportunity and braked hard, until the wee end of the stopping, the brakes went absolutely numb (like yours) and there were hardly any brakes. I achieved what I wanted to and by then my car had slowed down to around 20 kmph too so I just let it roll into the signal without touching the brake pedal ( allowing it to cool down). After the 90 seconds the signal had got over and brakes had cooled down by then and when I went ahead and tapped them again, they were as good as new.

No need to get anything checked, trust me. Just be careful next time you brake, to not continuously hammer the brake pedal with the foot on it throughout the braking time, let it off for a split second and brake again. Of course in case you have to brake like there is no tomorrow, you have to jam the brake pedal and if the brakes lock (If your car has no ABS), then its fine, the braking won't be lost as the pads are not being overheated by a constant friction, but are locked in position on the disc but during these high speed long brakings, make sure you let the foot off for a split second and then back on braking again.

My 2 cents.
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Old 20th March 2014, 18:45   #14
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Default re: Strange loss of braking ability. What happened?

Quote:
Originally Posted by msdivy View Post
I felt loss of steering control along braking control. Thats why when I stopped first thing I did was to check if wheels are in place.
Loss of steering control along with loss of braking ability happens only when tyres lock up under hard braking and start skidding in a non ABS equipped vehicle.

I suspect tyres lost traction briefly due to slippery road surface. Maybe oil or some such slippery stuff was spilt on the road. In a such a situation, as a driver, we have to instinctively pump the brakes, modulate braking force and hope for the best. If you keep pressing the brakes harder you will never get any traction as the car is sliding already. By letting go of the brakes you are allowing the tyre to roll on the road. Now grab the brakes again so that the tyres, this time, grab hold of the road. All this needs to be done in a matter of miliseconds of course. Sounds too difficult? get a car equipped with ABS.
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Old 20th March 2014, 19:01   #15
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Default re: Strange loss of braking ability. What happened?

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Originally Posted by Santoshbhat View Post
All this needs to be done in a matter of miliseconds of course. Sounds too difficult? get a car equipped with ABS.
And also with tension in the back of the mind and building pressure from members in the car.

Getting a safer car is better than repeating such an incident!

Anurag.
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