Hello i have a 2005 bmw 745LI and its saying on the dash ...
Customer
Hello i have a 2005 bmw 745LI and its saying on the dash [brake](/topics-brake/) drive malfunction i reaplace the master cylinder and brake power booster and the vacuum pump and that portion is fine however if i try to drive, all ...
Hello i have a 2005 bmw 745LI and its saying on the dash [brake](/topics-brake/) drive malfunction i reaplace the master cylinder and brake power booster and the vacuum pump and that portion is fine however if i try to drive, all the brakes is locking up on its own and would not drive.
Mechanic's Assistant: Have you checked the fluids recently?
Yes i change the master cylinder and it have new brake fluid and its full
Mechanic's Assistant: What is the model of your '05 BMW?
745li
Mechanic's Assistant: Are you fixing your 745li yourself? What have you tried so far?
I change the battery and check the alternator output which is good
Mechanic's Assistant: Anything else you want the Mechanic to know before I connect you?
The brake switch was causing the brake light to remain on but i adjust the switch and its working fine now.
Read More
Responses
Daniel
251 days ago
Automotive Expert
Hi. I'm Daniel,
I'll be the mechanic assisting you today.
I'm sorry to hear about the problems you have with your 7 series.
Let's see if we can figure this out and get you back on the road quickly.
What codes are stored in the system if you scan it with a capable diagnostic scanner though the OBD2 port?
As soon as the a warning sign appears on the dash, the system does also store one or several fault codes that give us further indication on what triggered the fault.
Possible cause I can see at this point is the hydro-unit for the DSC. This is the only part I can see that is locking up ALL brakes together at the same time.
Customer
251 days ago
Customer attachment 1/25/2021 1:16:26 PM
Customer
251 days ago
This what i saw when my friend scan the car5EFE pressure sensor offset and 5FOE Yaw rate sensor can error
Daniel
251 days ago
Automotive Expert
The Yaw rate sensor fault can not cause this.
Good possible that the DSC unit is locking up and this also sets the pressure plausibility code.
The hydro-unit is actually the only part that can cause all 4 brakes to lock up at the same time.
Customer
251 days ago
Is that the abs module ?
Daniel
251 days ago
Automotive Expert
Yes, the ABS module is attached the hydro-unit and it comes as one piece.
Customer
251 days ago
Ok is there anything i can do to bypass the system until i can buy one ? And also could replacing the master cylinder and brakes booster and repairing the vacuum pump trigger this issue because before i did the repairs i was not getting this issue ?
Daniel
251 days ago
Automotive Expert
I'm not aware of any measure to bypass the ABS.
However I understood that the issue was present all along and that replacing the master cylinder& brake booster did not solve the issue.
Good possible in this case that the master cylinder is causing this and is maybe not adjusted properly etc.
Why were the parts replaced anyway as they can not cause the warning lights you experience as well?
Customer
251 days ago
No actually the issue i had at first was the brake pedal was hard and it had oil and brake fluid in the brake booster and was not getting sufficient vacuum thats why i replace the parts after i did the job the car drove perfect that night although i had a bad battery that was reading 6.5 volts the next day thats when the problem start happening so i bought a new battery thinking that was the problem.
Daniel
251 days ago
Automotive Expert
The lockup of the brakes are either caused from the hydraulic-unit that is part of the ABS or either the master cylinder& installation.
I can not see a electrical cause at the moment.
Customer
251 days ago
Ok thanks
Daniel
251 days ago
Automotive Expert
You are welcome.
Please let me know if I can provide anything else at this point.
Customer
251 days ago
Will do thanks Daniel .
Daniel
251 days ago
Automotive Expert
You are welcome.
Thanks for using JustAnswer.
Still not sure what you need?
Have a certified mobile mechanic diagnose what's wrong with your car, at your home or office.
Hello, brakes being one the most important systems on the car, this should be handled sooner rather than later and the vehicle should not be driven. I am unclear as to why you believe the caliper should have been replaced....
Hi there. Sounds to me that you will need your radiator swapped out for a new one. Some supplementary things that go along with this repair are: a new water pump, radiator cap, hoses, and also a new thermostat. This...
Hi. If your car is suffering in performance and the wrench indicator light has come on, then that means the vehicle needs to be serviced. A professional technician, such as one from YourMechanic, should be able to scan the vehicle...
Have a trained mechanic first verify a proper oil level. This is vital to the engine's operation, as internal components that are not receiving proper oiling can become noisy. If the noise doesn't go away with the proper oil level,...
Hey There: Sorry to hear about the problem you're experiencing with your 97' Pontiac Firebird. What you're describing actually happened to an acquaintance of mine last year. He tried every trick in the book, including the "gas in the spray...
Hi there, thanks for writing in about your 1995 Ford F-150. You would need to check to see if you have fuel pressure at the fuel rail. If you have pressure and spark, but it will not stay running, then...
You may have a dirty or failing idle air control valve. The idle air control valve reads the air intake as it is mixed with fuel prior to being injected into the engine at low speeds and at idle. Since...
When routine service or maintenance is due the ECU activates this warning light to let you know. However, in most cases, the light needs to be cleared after the service manually. If you look in your owner manual, you should...
Hello. There is no fuel line kill switch for your particular vehicle. There is a fuel pump fuse which can act as a fuel line kill switch. It is located in the rear compartment fuse box. The rear compartment fuse...
Hello i have a 2005 bmw 745LI and its saying on the dash [brake](/topics-brake/) drive malfunction i reaplace the master cylinder and brake power booster and the vacuum pump and that portion is fine however if i try to drive, all ...
Hello i have a 2005 bmw 745LI and its saying on the dash [brake](/topics-brake/) drive malfunction i reaplace the master cylinder and brake power booster and the vacuum pump and that portion is fine however if i try to drive, all the brakes is locking up on its own and would not drive. Mechanic's Assistant: Have you checked the fluids recently? Yes i change the master cylinder and it have new brake fluid and its full Mechanic's Assistant: What is the model of your '05 BMW? 745li Mechanic's Assistant: Are you fixing your 745li yourself? What have you tried so far? I change the battery and check the alternator output which is good Mechanic's Assistant: Anything else you want the Mechanic to know before I connect you? The brake switch was causing the brake light to remain on but i adjust the switch and its working fine now.