2009 Mazda 6 braking Problem Question

[Omodan]

After doing a quick search I cant seem to find someone who has asked this question before so here goes.

I purchased a 2009 Mazda 6 Grand Touring with everything available except the navigation system. It is a great car except for a problem I have been experiencing with the brakes.

The brake appears to be automatically engaging itself while driving. I will not have my foot on or even near the brake pedal. In some instances my foot will be on the gas, yet the brakes appear to also be and stay engaged.

It begins as a slight vibration through the car and gradually increases. I have to depress the gas pedal more just to maintain the same speed. Eventually the vibration becomes so significant that you cant see out the rear view mirror due to it shaking so badly. If I depress the brake and then release, the vibrations stop.

I have also noticed that I cannot turn on cruise control at times. However, when this happens, I can depress the brake and release, and then engage cruise control. This also makes me think it is the brakes since I know you cant engage cruise control when your foot is pushing on the brake.

Lastly, my wife has traveled behind me in our other vehicle and noticed that my brake lights will turn on and remain on for extended periods of time. The will remain on until I am forced to brake, such as a stop sign or light. By extended periods of time, I mean at least 10 miles or more.

I had one incident when every indicator on my dash related to brakes went off. This occurred right after the vibrations became so significant that my car jolted. Basically every braking system in the car shut off and left me with manual brakes only. When I brought it to the dealer, they stated that they felt the battery ground wire was loose and tightened it. They then reset my fault codes. My indicators have never sense gone off since, which has made this problem quite annoying. Mainly because in the four subsequent times I have brought my Mazda 6 into the dealership, they state they cannot replicate the problem. I asked them to check the fault code history for the car but was told those are not stored in their system. They did state it sounded like a drive train issue and reset/reloaded the power train CPU. That did not fix the issue.

Since I cant seem to get them to experience the problem, I am at a loss of what to do next. I can only assume either a braking sensor is going bad or the CPU/Software that controls the brakes has a problem. Since this deals with the brakes I am fairly concerned. Any suggestions?

 

[Antonio DiMarco]

Sounds like defective/bad part(s)

After doing a quick search I cant seem to find someone who has asked this question before so here goes.

I purchased a 2009 Mazda 6 Grand Touring with everything available except the navigation system. It is a great car except for a problem I have been experiencing with the brakes.

The brake appears to be automatically engaging itself while driving. I will not have my foot on or even near the brake pedal. In some instances my foot will be on the gas, yet the brakes appear to also be and stay engaged.

It begins as a slight vibration through the car and gradually increases. I have to depress the gas pedal more just to maintain the same speed. Eventually the vibration becomes so significant that you cant see out the rear view mirror due to it shaking so badly. If I depress the brake and then release, the vibrations stop.

I have also noticed that I cannot turn on cruise control at times. However, when this happens, I can depress the brake and release, and then engage cruise control. This also makes me think it is the brakes since I know you cant engage cruise control when your foot is pushing on the brake.

Lastly, my wife has traveled behind me in our other vehicle and noticed that my brake lights will turn on and remain on for extended periods of time. The will remain on until I am forced to brake, such as a stop sign or light. By extended periods of time, I mean at least 10 miles or more.

I had one incident when every indicator on my dash related to brakes went off. This occurred right after the vibrations became so significant that my car jolted. Basically every braking system in the car shut off and left me with manual brakes only. When I brought it to the dealer, they stated that they felt the battery ground wire was loose and tightened it. They then reset my fault codes. My indicators have never sense gone off since, which has made this problem quite annoying. Mainly because in the four subsequent times I have brought my Mazda 6 into the dealership, they state they cannot replicate the problem. I asked them to check the fault code history for the car but was told those are not stored in their system. They did state it sounded like a drive train issue and reset/reloaded the power train CPU. That did not fix the issue.

Since I cant seem to get them to experience the problem, I am at a loss of what to do next. I can only assume either a braking sensor is going bad or the CPU/Software that controls the brakes has a problem. Since this deals with the brakes I am fairly concerned. Any suggestions?

If it was software then it would be common to all Mazda6's

I would try another dealership to try and root cause the issue and if that doesn't work contact Mazda directly. I don't quite understand what they mean by the "fault codes are not in their system". Do they mean the car's computer does not retain them.

Bottom line this is a safety issue and needs to be solved. If it happens as often as you say then the dealer should take it for a week and try and replicate it over days not minutes or hours.

Did you by chance buy it new or used? Where are you located?

 

[Omodan]

They told me that they clear the codes from the car and the car itself does not retain past codes. I then asked if they kept the codes in their maintenance computer there at the shop, and they stated no. I was surprised by this since they track my oil changes and maintenance schedule, but don't retain history of complaints and codes the car had when I brought in.

The car had 7 miles on it when I purchased it. The problem started pretty much that week and has been consistent since. It now has 18,000 miles on it now.

The problem is not as pronounced as it was, but is still present. I wonder if maybe the thickness of the pad is playing into it. Ill try as you suggest and bring it to a different dealer.

The car was purchased in Antioch Tennessee and maintenance there as well. The next closest dealership is in Franklin Tennessee.

 

[Omodan]

One more thing. After doing a little reading about the braking systems in the Mazda 6, i came across the DSC button and that system's purpose.

I have noticed that when the vibration starts, while traveling on the interstate and i cannot engage the cruise control, if i press the DSC button and turn that system off, the vibration stops and i can now engage cruise control.

The dealer does not know this yet, so ill let them know and see if they helps them figure it out. On a side note, its hard to replicate because it usually only happens on long hauls on the interstate, approximately 25 miles or more of not having to brake. So i doubt anyone doing just local town driving would experience this issue as any time you press the brakes resets whatever system is causing the brakes to engage. I know just around town, i dont experience it. Only interstate driving to and from work. (50 miles one way)

 

[mnthny4]

u may need to replace faulty brake hydraulic unit & control module ,u have a faulty brake pressure sensor which is a part of the hydraulic unit ,get the dealer to replace that & u should be good to go ,note have them check electrical wiring harness for DSC function .good luck.

 

[PJM]

Dealerships Seem To Be Following The Company Line a la Toyota

After doing a quick search I can’t seem to find someone who has asked this question before so here goes.

I purchased a 2009 Mazda 6 Grand Touring with everything available except the navigation system. It is a great car except for a problem I have been experiencing with the brakes.

The brake appears to be automatically engaging itself while driving. I will not have my foot on or even near the brake pedal. In some instances my foot will be on the gas, yet the brakes appear to also be and stay engaged.

It begins as a slight vibration through the car and gradually increases. I have to depress the gas pedal more just to maintain the same speed. Eventually the vibration becomes so significant that you can’t see out the rear view mirror due to it shaking so badly. If I depress the brake and then release, the vibrations stop.

I have also noticed that I cannot turn on cruise control at times. However, when this happens, I can depress the brake and release, and then engage cruise control. This also makes me think it is the brakes since I know you can’t engage cruise control when your foot is pushing on the brake.

Lastly, my wife has traveled behind me in our other vehicle and noticed that my brake lights will turn on and remain on for extended periods of time. The will remain on until I am forced to brake, such as a stop sign or light. By extended periods of time, I mean at least 10 miles or more.

I had one incident when every indicator on my dash related to brakes went off. This occurred right after the vibrations became so significant that my car jolted. Basically every braking system in the car shut off and left me with manual brakes only. When I brought it to the dealer, they stated that they felt the battery ground wire was loose and tightened it. They then reset my fault codes. My indicators have never sense gone off since, which has made this problem quite annoying. Mainly because in the four subsequent times I have brought my Mazda 6 into the dealership, they state they cannot replicate the problem. I asked them to check the fault code history for the car but was told those are not stored in their system. They did state it sounded like a drive train issue and reset/reloaded the power train CPU. That did not fix the issue.

Since I can’t seem to get them to experience the problem, I am at a loss of what to do next. I can only assume either a braking sensor is going bad or the CPU/Software that controls the brakes has a problem. Since this deals with the brakes I am fairly concerned. Any suggestions?

I have a similar 2009 Mazda 6i Grand Touring with 8500 miles. I purchased the car in January of 2009 new. I have brought my Mazda 6 in more than 5 times with a similar vibration and I am getting the same attitude from the service department - Basically, they say either that is the way the car is or it is in my mind. I brought it in just last week and I had them test drive it. Now as I am coming to a stop and the automatic transmission shifts down it feels like the car is bucking as it goes into 2nd or 1st.

Mazda's service department new excuse is that the car is so computerized that if a warning light doesn't go on there is nothing wrong with the car.

I have also felt that the brakes are sticking and I often look to see if I have completely released the hand brake.

I am just this far from constructing a BIG LEMON and parking it outside the dealership.

There is definately something WRONG with all these MAZDA 6 and MAZDA and it Dealerships are trying to COVER UP.

I think MAZDA is turning into another company like TOYOTA!!!!

 

[PJM]

Just took my 2009 Mazda 6i to the dealership to meet with the regional Mazda rep.
Have similar problems but not as severe as yours. I have a constant drag as if my hand brake is on and I have an intermittent bucking feeling when I ease of the accelerator. Plus it rides like a buckboard.
The regional rep drove the car couldn't feel anything . . . of course.
But at least I have it on the record.
Ready to dump the car with only 10,000 miles on it.

 

[chalex]

Same Problem!!

I am experiencing exactly the same braking problem as all of you. I bought it new, have been driving it for almost 2 years now and the problem started about a month ago @ 25,000miles or so. No problems with the cruise control though. I live in Monterrey, Mexico, so definetely this is a broader problem and needs to be brought to mazdas attention!!