Here is an applicable TSB:

https://static.nhtsa.gov/odi/tsbs/20...44540-1228.pdf

"SOME 2010-2012 ESCAPE/MARINER HYBRID VEHICLES MAY EXHIBIT THE RED BRAKE LAMP ILLUMINATING ACCOMPANIED BY DIAGNOSTIC TROUBLE CODE C1015, C0101C OR P1A1B WITH NO CHANGE IN BRAKE PEDAL FEEL. THIS MAY BE DUE TO A LEAK IN THE INTERNAL CHECK VALVE CONTAINED IN THE "TEE" OF THE 9C482 VACUUM HOSE. ORDER A REPLACEMENT 9M6Z-9C482-C VACUUM HOSE WHICH CONTAINS A REDUNDANT CHECK VALVE."

By far the lowest-cost option right now (since you know your pump is spinning - you can hear it! and your brake booster is WORKING), is to replace the 9M6Z-9C482-C assembly. Nobody seems to have a clear picture all by itself but that doesn't surprise me in 2021. If you order one from a Ford dealer or go online make sure it's the full, correct part number, and swap that baby out. $100 or so. Then if it doesn't work, you're looking at more money. Your brakes are working and your pump is working, and your description of the problem closely matches the TSB, so I have a hunch that's 100% of the problem. I think they want to charge you $1500-1600 to fix an $85 part that would maybe get them another $70-$100 in labor. Much better for you to spend that much from their point of view and kill four birds with one stone.

 

That little valve costs so much? You can just take one from wrecker, I don't remember getting charged for my filler neck even because they don't know how to price it and don't care. I got battery bolts and fuses for free too. This is like a prime candidate. Ford are ****** again and want you to buy all new hoses from the look of it. With brakes out getting there might be another thing all together.

 

It's not the valve alone, Ford sells it as an assembly with the hoses. I cannot find a listing for the valve and T by itself. But you're right, it could be even cheaper. In the video it looks like a pretty common check valve-T assembly. I don't know where the OP lives, but maybe asking a friend for a trip to the boneyard with the promise of an overpriced Quarter Pounder Deluxe + fries and paying for the gas would get them there and back with the answer that fixes the car. All things are possible As the Wrench Turns.

 

Hey Guys,

Just wanted to give an update, ordered part 9M6Z-9C482-C - VACUUM HOSE WHICH CONTAINS A REDUNDANT CHECK VALVE. I Will put it in myself and will update after!

Thanks again for being an amazing community.

 

Great! Fingers crossed this solves the problem completely and at a relatively good ((cost*grief)^2)/(effectiveness)) ratio. Good luck and let us know how it goes.

 

Hey guys,

Got the part and looking at replacing the hose/check valve hose. All are easily accessible, except the vacuum pump itself - in the video, he shows it's easy to access the electric connector, but I removed the guard below, and it looks like this hose will run potentially to the top of the vacuum pump - will I have to remove the vacuum pump in order to do this? and if so, any tips?

Thank again,

D

 

I pulled the entire T out at the top without messing with the pump. Came free from all the hoses. If you need to change one you might have to take the pump down.

 

Gotcha. Yeah, I don't have the tools/experience to get that pump out. So I did what you did. Left the hose going to the pump, and replaced all the others including the T check valve.

Thanks again for the advice guys, will drive it around and give you an update, fingers crossed it was the check valve!

D

 

My abs problem was air in the lines but I had to test that check valve since it was such a common problem. BTW, you can see all 4 individual brake pressures in scanning software which is new to me but a cool way to see what's wrong.

 

Good luck and let us know, hoping this aces it and you don't have to dig deeper.