Complete Brake Failure -- Thanks Toyota!

Follow up on 8/19 10pm ET..

Here is the update... and yes, why I am mad at both Toyota and the dealership.

Yes, the car (2005 4R Sport, 65K miles) was towed.

The Master Brake Cylinder did fail and there was no way to stop the car without using the parking brake (best option) or taking it out of D. The brakes went completely out. I was in the car - the entire dash lit up, and the car was closing in the student driver in front of my daughter. Opposed to hitting another car, we just needed to stop the car! I could have cared less about the tranny or parking brake - I was just glad she did something instead of nothing! The brake pedal hit the floor with zero resistance when she tried to stop the car. Again, thankfully this did not happen on the open road - stop sign, red light, school crossing, highway -- the list goes on!!!!!!

So, why am I mad ? We did not blow this off. We had heard an oscillating sound from the engine compartment for 2 years. Every time we told the dealer about it and they just said it was nothing to worry about... the car was just getting older. I thought is was the AC. It was not until 4 months ago that they noticed an error code on the ABS systems, but said this was not related to the braking system. I did call Toyota Customer Care and they said the same thing the dealer told me. The car was safe to drive - if the ABS fails, the brakes will work fine. I should mention that the ABS was still working fine so I had no reason to believe this car was unsafe - I thought both the dealer and Toyota CC had given me sound advice and that I would just have the ABS fixed if and when it failed.

With this said, if I was told this car was unsafe or there was a risk the brakes could completely fail, I would have fixed or traded it in without giving it a second thought.

Net/net is that this was a bad situation that could have been worse -- much worse regardless of the driver behind the wheel.
 
I say BIG TIME kudos to the inexperienced driver for having the presence of mind to throw it in Park and stopping the vehicle.

Most would have just pushed harder on the brake pedal while their brain tried to comprehend the ineffectiveness of their action; even experienced drivers.
 
I say BIG TIME kudos to the inexperienced driver for having the presence of mind to throw it in Park and stopping the vehicle.

Most would have just pushed harder on the brake pedal while their brain tried to comprehend the ineffectiveness of their action; even experienced drivers.

I couldn't agree more.
 
This is exactly why I called Toyota CC. It did not make any sense.

Called CC? WTF? You were the one that authorized the service. So if you went to the Doctor with a broken toe, you are going to let them give you an asthma inhaler and call it a day?

Come on man, come clean. You are making this up.
 
If anyone is thinking the parking brake is an option be sure to test that theory before deciding that it is plan A for a brake failure.
 
Called CC? WTF? You were the one that authorized the service. So if you went to the Doctor with a broken toe, you are going to let them give you an asthma inhaler and call it a day?

Come on man, come clean. You are making this up.

I wish that was the case. Maybe the thermostat had gone bad, but I was skeptical because the car never overheated. Nevertheless, this dealer had been extremely reliable until this situation. I had no reason to doubt this solution until we picked up the car and oscillating sound was still there -- and to your point, that is why I did not call it a day and just accept the solution. I called to CC to see this the was a common problem, if there was a TSB and get some advice. If your toe is broken, you will know it - I had no idea the MBC was failing, thus put my trust in the dealer to fix the problem. I guess Caveat Emptor in play.

The biggest mistake I made was not searching this Forum 4 months ago. This is not the first time this model as had a MBC failure. Rare, possibly yes.... but it has happened before with the exact same symptoms my car had experienced. If I had looked, I could have pointed the dealer to the possible cause. Lesson learned.
 
If anyone is thinking the parking brake is an option be sure to test that theory before deciding that it is plan A for a brake failure.

No, the MBC failed. The car was inspected by a different dealer on Saturday. They have not pulled the unit to find the exact cause, but will in the coming days.
 
This is a tough situation but it sounds like things were mild compared to what could have happened.

I'm not sure if someone could predict a master cylinder failure.

I will agree the whole thermostat replacement is strange.
 
usually an MC failure has warnings.
but, when its an integrated unit, the pedal may not do anything weird until the faliure.
im a fan of toyota, but im not a fan of stupid. an integrated MC/ABS/booster is stupid. too many critical systems with one failure point.
 
What else is the EMERGENCY brake for?

Again, and again...it is not an 'emergency brake'...not any more...It is a parking brake. Using it in a bad situation can make things worse...that's why it is no longer called an emergency brake.

Back to the subject at hand...sounds like you had a total failure of the master cylinder, which is unusual since it has dual independent chambers...sort of a redundancy...if one side goes out you still have the other.

For both sides to go out, something must have damaged the pistons/seals...you mention the brake fluid was replaced. Was this service done by you or did you pay someone?

I'm thinking you got some contaminated or wrong fluid (DOT 5 vs. DOT3/4) in the system...

But glad to hear no one got hurt...
 
Again, and again...it is not an 'emergency brake'...not any more...It is a parking brake

I agree it's no longer called the emergency brake...But guess what...if my brakes fail I'm going to use the parking brake to make an emergency stop. While it may not be called an emergency brake it's about the only option you have.
 
What else is the EMERGENCY brake for?
As has been stated already, the term "Emergency Brake" is no longer correct. These days, Parking brakes are weak and are only meant to hold the vehicle at a stop, hence why even in a honda you can overpower your parking brakes. They just aren't built to stop such heavy modern cars anymore.

Having taken apart my old Hydraboost unit, I find it difficult for the unit to have failed hydraulic 100%, but it is not impossible. Looking at the design, if you're saying the unit was continuing to attempt to pressurize the acumulator. It is possible, there was a hydraulic failure somewhere in the high pressure circuit that caused it to simply bleed back into the system, providing no real pressure. I will take a look at my unit again, since it is dissasembled to see if my idea is correct.

That being said, it sounds like the Dealer and Toyota CC was both correct and wrong in their advice. They are right, if the ABS portion failed, it will not normally affect the braking, usually the solenoids are actuated closed to provide braking pressure. So a hydraulic failure due to that system is unlikely. BUT, that doesn't mean a failure in the ABS Unit or potetional noise or pressure issue being caused by that portion of the system couldn't cause a failure in the rest of the unit.

I'm a little surprised that they did not explain that, I would think at least the technicians would be able to explain the system better, but then again; they report to the service writers who have to often "dumb it down" for customers and a lot of times important information gets excluded for the sake of simplicity. :(

In any case, I would talk to Toyota CC, they do seem to have been responsible for providing misleading information that did not help the vehicle get repaired.

To tell you the truth, this is the first time I have heard of a HydraBoost unit failing hydraulically 100%, but like I said, its not impossible.
 
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Again, and again...it is not an 'emergency brake'...not any more...It is a parking brake.

But glad to hear no one got hurt...
If you have complete failure of your brakes you're really not left with a lot of other options. I can assure you that it can stop a car that's moving. You think the government would let cars drive on the road with a brake system that has no back up? It has more than enough power to slow you down.
I agree it's no longer called the emergency brake...But guess what...if my brakes fail I'm going to use the parking brake to make an emergency stop. While it may not be called an emergency brake it's about the only option you have.
What I was getting at.
 
So when you first heard the ABS/Brake Everything system cycling through before turning over the ignition, how long did it cycle through before shutting off?

Mine does it for 15-30 seconds then turns off. Then as I pull away from my driveway, I may hear it click over a few times then it I never hear it again.
 
So when you first heard the ABS/Brake Everything system cycling through before turning over the ignition, how long did it cycle through before shutting off?

Mine does it for 15-30 seconds then turns off. Then as I pull away from my driveway, I may hear it click over a few times then it I never hear it again.

It was intermittent at first, but you could hear it occasionally when at a stop light. Over the past year, it was more prevalent which is why we brought the car in to get checked -- more than once. The system was in cycle mode all the time.

It has been so long since our car was 'normal' - I am not sure if what you are hearing is normal or not. Maybe another Forum member can chime in.
 
It was intermittent at first, but you could hear it occasionally when at a stop light. Over the past year, it was more prevalent which is why we brought the car in to get checked -- more than once. The system was in cycle mode all the time.

It has been so long since our car was 'normal' - I am not sure if what you are hearing is normal or not. Maybe another Forum member can chime in.

This is what mine does...

Take note of the fluid reserve (goes down). Cycles from 8 seconds - 33 seconds. So, 25 seconds.

4Runner HydraBoost System Noise - YouTube
 

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