cancel
Showing results for 
Search instead for 
Did you mean: 

electric brake booster

mikemc53
Explorer
Explorer
I have a 2004 HR Vacationer (Ford V-10) that has an electric brake assist system. The brake booster motor runs constantly with the key in the on position and I was wondering where to look to fix this. My guess is that it would only need to run when the brakes are applied but it seems to run all the time.

I bought the vehicle last summer and it has always done this - I have just ignored it because I really didn't know what it was until the other day. When turning the key to "on" before starting I would hear it but, normally, couldn't hear it after start due to the engine noise. Well I wanted to do a 5 Star tune on the coach and leaving the key "on" was really loud without the engine running - also I think this booster is keeping the 5 Star from working because I am not getting vehicle info nor is it connecting (error message 110B8). I would like to fix the booster issue for a couple of reasons, not the least of which is the fact that a constantly running motor is not necessarily a good thing.

Thoughts?
2021 Gulf Stream Conquest 6250 (Class C)
10 REPLIES 10

DrewE
Explorer
Explorer
tragusa3 wrote:
Sorry. I hear the hydroboost buzz when I put the key to the on position. Once I start the engine and while driving, I do not hear the buzz.


That sounds like proper operation to me, based on what I remember of how the system works (which may not be quite precisely right). There's no need for the electric back-up booster pump to run when the engine is running and the power steering pump is pumping.

10forty2
Explorer
Explorer
tragusa3 wrote:
Sorry. I hear the hydroboost buzz when I put the key to the on position. Once I start the engine and while driving, I do not hear the buzz.


Seems to be the way it works....our 1999 HR does it too! When the key is on, but engine not cranked...as in when deploying stabilizers...the annoying buzzing is there. When key is not turned, no buzz unless you press on the brake pedal. When cranked, it makes no noise at all. Had brakes system bled 3 years ago when I replaced the brake lines and calipers....buzzed before and after, so I gotta guess it's the way it's designed to work.
1999 Holiday Rambler Endeavor, 36' Gasser
Triton V10, Ford F53 Chassis
-----------------------------------------

tragusa3
Explorer
Explorer
Sorry. I hear the hydroboost buzz when I put the key to the on position. Once I start the engine and while driving, I do not hear the buzz.
New to us 2011 Tiffin Allegro Open Road 34TGA
Join us on the road at Rolling Ragu on YouTube!

wolfe10
Explorer
Explorer
tragusa3 wrote:
Following. Our "new to us" coach has always done the same. I'd never owned one before and assumed it was normal. Braking seems to work fine.


Sorry, not clear on what you mean.

Does your hydroboost work all the time the ignition is on (OP's coach) or only when you press the brake pedal?
Brett Wolfe
Ex: 2003 Alpine 38'FDDS
Ex: 1997 Safari 35'
Ex: 1993 Foretravel U240

Diesel RV Club:http://www.dieselrvclub.org/

tragusa3
Explorer
Explorer
Following. Our "new to us" coach has always done the same. I'd never owned one before and assumed it was normal. Braking seems to work fine.
New to us 2011 Tiffin Allegro Open Road 34TGA
Join us on the road at Rolling Ragu on YouTube!

Robert_F_K
Explorer
Explorer
I have a good manuel with trouble shooting. Is there a way to attach the file here
Bob

PastorCharlie
Explorer
Explorer
I have the hydro boost brake system and the electric motor only runs when the brake pedal is pressed.

don_lou
Explorer
Explorer
Deleat
Don & Louise

DrewE
Explorer
Explorer
I think these use hydroboost brakes, with the electric backup for the main power steering pump. It sounds as though the pressure from the power steering pump is not making it to the brake system for some reason; if the power steering seems to be operating normally, I might guess (and it's purely a guess) that there's a problem with the valve system for the hydroboost brake accumulator...or perhaps a bad switch to turn the auxiliary pump on and off.

At first glance it would not appear to be related to the five star tune problem, but I don't totally discount that possibility. Vehicle systems are not always obvious in their interactions and failures!

MountainAir05
Explorer II
Explorer II
When is the last time you bleed the brake system. Sounds like it low on fluid.