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Discussion Starter #1 (Edited by Moderator)
Is this catastrophic brake failure?

I was driving home on the expressway, luckily it wasn't moving fast. Out of nowhere with no indication, I pressed on the brake pedal and it went to the floor. There is no brake warning light indicator and it required me pumping the brakes to get the car to stop. At this point, I was in stop and go traffic and I let the car in front move about 5 car lengths out and I got it up to 20mph and it was like I was stopping on ice, almost zero response.
I pulled the car on the shoulder and had it towed home from there.

Checking the car over at home, fluid levels are good, fuses are good. I disconnected the battery for half an hour and it's still the same problem.

The scary part is that the brake light indicates no issues.

I am thinking about contacting a lawyer before taking her into the dealer. Thoughts? 馃
 

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First, don鈥檛 forget you have an emergency brake for just this eventuality. I think you may want to determine a cause before you jump to conclusions with a lawyer.
 

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Discussion Starter #4 (Edited by Moderator)
I did have to use the emergency brake, but it was pretty scary since there are no dash lights indicating an internal issue. My concern is that Dodge sweeps this under the rug, since based in the service manual there should be some fail safe light coming on for these issues.
 

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Brakes are a mechanical system so unplugging the battery for 1/2 hour (honestly 10 seconds is enough for adaptives to be reset) won't do a thing for them. You are the first person I have read about having this issue so I don't think it is a big FCA conspiracy. What is interesting and troubling is you had no brakes at all. If the oil level was fine then the master cylinder seals must have completely given out or fault ABS module? But if there was a leak your fluid level would be low. Looking forward to what the dealership finds.

A quick search shows one member with a 2009 having brake failure but the behavior of the pedal does not appear to be the same as you experienced.
 

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There is a separate front and rear brake system both operated by the foot pedal. Pressure loss in one system will cause the brake light to turn on. I am interested in what turns out to be the cause. It is possible, but unlikely, that both systems failed but I don't know the circumstances around the event so I won't venture any kind of guess, even though I have a couple in mind.
 

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Is this catastrophic brake failure?

I was driving home on the expressway, luckily it wasn't moving fast. Out of nowhere with no indication, I pressed on the brake pedal and it went to the floor. There is no brake warning light indicator and it required me pumping the brakes to get the car to stop. At this point, I was in stop and go traffic and I let the car in front move about 5 car lengths out and I got it up to 20mph and it was like I was stopping on ice, almost zero response.
I pulled the car on the shoulder and had it towed home from there.

Checking the car over at home, fluid levels are good, fuses are good. I disconnected the battery for half an hour and it's still the same problem.

The scary part is that the brake light indicates no issues.

I am thinking about contacting a lawyer before taking her into the dealer. Thoughts? 馃
That is a rare failure. The car should have a split brake system with 2 "master" cylinders -- just one long cylinder -- and each with its own piston. The braking can be a separate system for the front brakes and rear brakes, or there are other configurations.

I do not know how well the split braking system works if a failure happens. Based on what you wrote not very well it would appear.

Or the failure involved both split systems. Which might explain the poor performance of the split system.

The failure could be something that compromised both of the split braking systems. This has to be very very rare.

That the fluid level was ok suggests perhaps something mechanical failed but I'd have to see the master cylinder and its pistons assembly drawing to hazard a guess.

And the warning light is only triggered by a low fluid level.

There is another explanation. I vaguely recall -- this some years back -- my Dad telling me of a time when the brakes in his Suburban failed. I don't recall the severity of the failure although I know there was no accident thank goodness.

I seem to recall he had to have the vehicle towed. What was found to be the problem is when he had the vehicle in for service at some place far from home -- the Suburban was used to tow a camper trailer: Dad and Mom were in their RV'ing phase of retirement at the time; apparently someone topped up the brake fluid reservoir with the wrong fluid, oil of some kind. This over some time and miles caused the seals to fail. The master cylinder, and I think the Suburban might have had disc brakes at the front wheels so the calipers, and last but not least the wheel cylinders of rear wheel drum brakes all had to be replaced. Not sure if the brake lines needed to be replaced but if they were not I'm sure were flushed to remove any traces of the wrong fluid having been used.
 

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The brake warning light should illuminate if either brake subsystem leaks. There is a switch that is normally sprung in the middle separating the fluid of the front and rear. Pressure on one side of this switch will cause it to slide over, closing contacts that light the tell tale. In normal operation, this switch has pressure on both sides, so it stays put.
 

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Is this catastrophic brake failure?

I was driving home on the expressway, luckily it wasn't moving fast. Out of nowhere with no indication, I pressed on the brake pedal and it went to the floor...
Just curious, what was the weather at the time? Did the pedal go all the way to the floor and was there any resistance at all?
 

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The brake warning light should illuminate if either brake subsystem leaks. There is a switch that is normally sprung in the middle separating the fluid of the front and rear. Pressure on one side of this switch will cause it to slide over, closing contacts that light the tell tale. In normal operation, this switch has pressure on both sides, so it stays put.
Ok. But what if both sides have no or little pressure?
 

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Ok. But what if both sides have no or little pressure?
On the older systems, it was a pressure imbalance, I assume it is the same, so as long as they were equal, it probably wouldn't light up.
Also what year/trim, and how many miles, and what all has been changed on the car?
 

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Ok. But what if both sides have no or little pressure?
It would not light up. Assuming that there are no damaged parts like cut brake lines
or other mechanical failures, that would be a rare occurrence. You would get a light if fluid was low, or if one side had low pressure.
 

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Failed master cylinder? Or even more unlikely but possible failed linkage.
 
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No one was hurt and nothing was damaged which are the most important things. I may get blasted but I'm gonna say it. Contacting a lawyer before even letting the dealer look at the car shouldn't even be in your thought process. My guess is the master cylinder failed. I reckon we'll find out shortly and you'll be back out cruising.
 
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your power brake booster might have a failure - another item to be check is if the master cylinder is producing the correct line pressure or if there is a leak and air is present in the lines.

IIRC, a scan tool with the ability to read ABS / ESP might be able to see what line pressure(s) are present in the hydraulic system.

your '18 ought to be in the warranty period, unless you've exceeded 36k miles
 

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There is a separate front and rear brake system both operated by the foot pedal. Pressure loss in one system will cause the brake light to turn on. I am interested in what turns out to be the cause. It is possible, but unlikely, that both systems failed but I don't know the circumstances around the event so I won't venture any kind of guess, even though I have a couple in mind.
I would have to check to be sure but I thought our breaks were what they called double diagonal where 1 Reservoir works the left front and the right rear and the other Reservoir does the other so you'll always have one front and one rear brake

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I would have to check to be sure but I thought our breaks were what they called double diagonal where 1 Reservoir works the left front and the right rear and the other Reservoir does the other so you'll always have one front and one rear brake

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I was going to say that, never checked though. I remember my 1988 LeBaron was that way, one of the first that I knew of. An easy way to tell is look at the 2 reservoirs, if they are different sizes it is front/back, if they are the same size, it could be either way.
 
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