Good evening all,
this is my first post so excuse me if I am making many mistakes!

I have a 2011 Ford Escape hybrid with 126000 miles. I bought it used with 93000 miles and everything was perfect. Few months ago, like to many other users, the “check brake system” message showed up and the red parking brake light came on. I did not notice any change in braking, only that the hybrid dusty would not kick in. Once I turned the car off and on again everything was gone and the car was fine. This has been happening more and more often. I took it to a mechanic that specializes in hybrid vehicles and the found tens of old codes stored when scanning that all seemed to lead to the PCM but once cleared nothing came up and they could not replicate the issue and sent me home.
I am a bit worried since I need the car for work so I would like to know what you think it is to fix it!

thank you so much!

 

Hello,

I would start checking your break system for any maintenance. Check break fluid level, brake pads, emergency break pedal. I haven't cross an issue like this on my own but that is where I would start.

 

thank you! They checked everything and said the brake system was fine!

 

Well, I hope yours is still fine. Did any Diagnostic Trouble Codes get triggered? You should keep an eye on it because I have seen other posts that this seemingly false signal subsequently becomes an Anti-Locks Brakes System (ABS) Control Module / Hydraulic Control Unit failure. I am experiencing and trying to diagnose a similar problem with 2011 Lincoln MKZ Hybrid, which my research has found to be similar components as Fusion Hybrid and Escape Hybrid of that generation. At first, I did not experience any loss of brakes, and the dash message/light "Check Brake System" went away with the shut down (i.e., key off). The ABS warning light did not illuminate. The Check Brake System message returned a week later, and then again a third time another week later. I did not lose any braking power until the message returned a fourth time, and this time, the ABS light came on the dash, another light for traction/serviceTrack(as I recall), and I needed to use the hand/emergency brake to stop. I understand that these are among the systems that need electronic power when the gas engine is not supplying power/vacuum. Therefore, when the ABS control module fails, various Diagnostic Trouble Codes are triggered (e.g., low vacuum, signal plausibility failure, circuit voltage below threshold, signal amplitude below minimum). Apparently, this is an expensive repair.

Anyone else having similar "Check Brake System" messages with or without loss of braking?

 

You may want to research collapsing brake hoses for at least the Escape as it is a known failure point and many times leads to replacement of the HCU when really only the hoses needed replacing and system bled.

 

I have a different vehicle but I think most of the hybrids are using a Kelsey Hayes type ABS system. I ended up replacing the ABS assembly as a unit on my 09 Tahoe Hybrid. Replaced only the EBCM the first time which lasted about 6 months then the ABS pump itself failed. I think a large majority of vehicle owners have never changed brake fluid and apparently with these sophisticated ABS systems the critical internal valving can develop a galvanic coating and start sticking together once the fluid loses its additives, Eventually leading to a complete failure. Seeing some people on the internet recommending 30k interval brake fluid changes? I never even thought about that being needed but I will be doing that from here forward.
I just bled the brake in my old 2000 windstar but it may be too late as I already have an intermittent ABS light and the fluid was super grungy rusty coming out. Live and Learn. Note: I bought a salvage yard assembly for the Tahoe Hybrid because the part from GM is Obsolete and unavailable, i ended up with about 700 dollars in both the parts and a shop to replace and reprogram. Not too bad but I could have used that extra cash for something else..................

 

Is your brake system still fine? I had this exact issue for years with my 2010 Mariner Hybrid and could not find any information on what it could be, and definitely didn't trust the dealer to diagnose it. It was fine for months, then would come on. Months turned to weeks, weeks turned to days, and then it would happen within 5 minutes of driving. Turned out to be the three way check valve. Instead of paying $70 for an entire new valve and hoses (because I could not find the valve by itself anywhere) I used two $5 one way valves in each of the vacuum lines.(this remedy eventually appeared in another forum) Everything was working perfect for the past two months, and now I have the ABS light, EBrake light, wrench, and stability light on. I don't think it is related to my repair, and am hoping it's just the vacuum pump that went bad because no vacuum is coming from there any more. So if your problem presents itself again, it's probably the check valve.

 

Yes I have driven about 3k miles and everything is working properly now.
Note: On the GM two-Mode Hybrids it is an Active braking Electro/Hydraulic system with no vacuum involved at all.
Seems to be a fairly complicated and finicky system.
Not totally unexpected for some stuff to break and some issues to pop up at +231k and over 10 years old.
I guess I was most surprised that some parts are already obsolete and unavailable.

 

good video here by makuloco:

 

good afternoon everyone! I actually found on a random forum that there is a service billetin from Ford about a hose (hard to find) that connects three ways in the engine (not too sure where) and that is faulty from 2010-2012. Changing that should solve the issues.