Parking Brake Fault - Need Diagnostic Info

[mobrien118]

Please don't reply with "need to have it towed - dealer [something, something]..." This is a 22 GTPE w/ 50k+ miles and, with no warranty left, I'm not taking it there unless I absolutely have to. I'm not remotely close to that point yet.

I'm having the parking brake issue and looking for experiential information that is relevant to my issue. Here are my clues:

Onset: Hard into a righthand turn, MIGHT HAVE heard a slight pop (not sure) Parking Brake Fault warning appeared immediately.

Initial Symptom: Increasing frequency of "Parking Brake Fault" message while driving, but no locking while parked.

Temporary Remedy Attempt: Diagnose lefthand (driver's side) parking brake fault. Inspect connector - NO FRAYING OR SIGNS OF STRESS VISABLE. Disassemble connector, Inject silicone into back of connector (wire side), with plastic sheeting between silicone and strain relief clip, so it can still be removed in the future.

[Remedy was effective for about a week, then the error message started appearing again.]

Continuing worsening: Over the coming weeks, the error came back and appeared more frequently, sometimes requiring me to lay under the back of the car and wiggle the connector, turn the car off and on, then try disengaging again. Once this started taking, average, 3-4 tries, I decided to take the next steps.

Temporary (current) solution: unplugged driver side connector. So that I can drive the car, and at least have one wheel's parking brake engaged, I disconnected the faulty brake, which means I still constantly get the warning about the fault since the computer can't see it.

Diagnostic observations and educated guesses:

• The sudden onset leads me to believe something physically broke (a wire, circuit, etc.)
• The lack of visible wear/stress makes me think it is either upstream (on the harness) or inside the brake actuator assembly, itself.
• When wiggling the connector to resolve the issue, it seemed like actually wiggling the socket on the brake, itself, was more effective, while simply wiggling the wire rarely worked.
• Removing and reconnecting the plug never seemed to fix the issue (as would be expected if it were corrosion within the connection), but wiggling it did.

As you can see, I am feeling like this issue is inside of the brake actuator.

Questions to help me strengthen this diagnosis (My poll should cover these, for simplicity and to keep the thread clean):

• How common is it for problem to reside in the actuator, itself?
• How common is it for the harness to fail, with no visible signs of failure?
• Anything else I'm missing that could help me fully diagnose this issue?

Thinking about possibly switching the sides of the actuators and seeing if the problem follows the actuator. Not sure I want to risk getting stuck and needing a tow, though...

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[Teslaeata]

The problem sounds like it lies with the harness/es.

I heard reports the brakes can fault with brake applied which obviously leaves car immovable.

I was fortunate, mine faulted with brakes released so could continue to use the car.

I heard that once the dealer got my car in for the repair, they managed to get the brake applied before removing the harnesses and couldn’t get brake released so put their lift out of action while they eventually managed to get the brakes released.

I thought the harnesses were the subject of a recall.

If so, and you are able to take to dealer I would have thought they’d do it under a recall, free of charge.

 

[Mach-Lee]

Are you aware a TSB and CSP has been released for this common issue? The parking brake motor connectors will be replaced.

See: https://www.macheforum.com/site/thr...tronic-parking-brake-harness-connector.27496/

Please have the TSB performed by your dealer if you have issues.

 

[ajp1023]

I had the park brake fault on and off daily for a few weeks but everything was working fine... untill finally in a parking lot the fault showed again but this time the parking brake was stuck on.

Just on a hunch, before I called a tow truck i wanted to re-seat the connectors since I knew they had a TSB on them. I reached through the spokes of the rear wheels to reseat the electrical connectors for the electronic brake and BOTH sides had the connectors loose. One was slightly loose and one was completely unplugged. I pushed both connectors back in until they clicked and everything was fine since then. This was about a year ago.

 

[Mach-Lee]

I had the park brake fault on and off daily for a few weeks but everything was working fine... untill finally in a parking lot the fault showed again but this time the parking brake was stuck on.

Just on a hunch, before I called a tow truck i wanted to re-seat the connectors since I knew they had a TSB on them. I reached through the spokes of the rear wheels to reseat the electrical connectors for the electronic brake and BOTH sides had the connectors loose. One was slightly loose and one was completely unplugged. I pushed both connectors back in until they clicked and everything was fine since then. This was about a year ago.

Did a dealer work it before that? Almost seems like human error not clicking the connectors back in fully after performing the TSB on it.

 

[mobrien118]

Are you aware a TSB and CSP has been released for this common issue? The parking brake motor connectors will be replaced.

See: https://www.macheforum.com/site/thr...tronic-parking-brake-harness-connector.27496/

Please have the TSB performed by your dealer if you have issues.

That CSP expired over a year ago. It is a paid service and I'm not willing to pay a dealer to do it. Worst case, I do it myself (provided it doesn't require dropping the battery, because I don't have the equipment for that and won't buy it).

I had the park brake fault on and off daily for a few weeks but everything was working fine... untill finally in a parking lot the fault showed again but this time the parking brake was stuck on.

Just on a hunch, before I called a tow truck i wanted to re-seat the connectors since I knew they had a TSB on them. I reached through the spokes of the rear wheels to reseat the electrical connectors for the electronic brake and BOTH sides had the connectors loose. One was slightly loose and one was completely unplugged. I pushed both connectors back in until they clicked and everything was fine since then. This was about a year ago.

I did that multiple times and even made a temporary fix by reinforcing the stress point on the side that is failing (which shows no signs of stress, anyway) with silicone. This is useful information, overall, but, unfortunately, does not apply to my circumstance. I'm currently operating with just one side connected to avoid getting stranded.

 

[Mach-Lee]

That CSP expired over a year ago. It is a paid service and I'm not willing to pay a dealer to do it. Worst case, I do it myself (provided it doesn't require dropping the battery, because I don't have the equipment for that and won't buy it).




I did that multiple times and even made a temporary fix by reinforcing the stress point on the side that is failing (which shows no signs of stress, anyway) with silicone. This is useful information, overall, but, unfortunately, does not apply to my circumstance. I'm currently operating with just one side connected to avoid getting stranded.

Order the part and do the TSB then. You just need to take the wheel off.

 

[jmcbrew]

It’s the harness connector up under the frunk. I got the failure message and made a service appointment. However, the parking brake actually failed (on) one morning in my driveway. Ford sent a rollback and fixed it that day. Mine didn’t fall into the VIN range of the service bulletin, so it wasn’t covered, but the extended warranty that the original owner purchased covered all but $100.

 

[smoke20]

I’m joining the club. Got the Park Brake Fault Warning. I understand the brake could clamp up at anytime while parked (or fail to clamp)….but is there a risk of this happing while driving (stoplight)? Im in 2 pedal and auto hold off.

 

[JustSomeQuickGuy]

I also got the Parking Brake Fault error 2 weeks after my 3-year warranty expired on my 2023 while driving down the road.

It ended up being code c2006 open in the left rear parking brake actuator. They ended up replacing it (the Ford mechanic said there was corrosion)

The part was $28, labor was $437.

 

[smoke20]

I guess get ready for the other side to fail next.

 

[BillTinVT]

I got this error, Park brake fault Service Now, while driving down the highway on a snowy Christmas morning ~100 miles into my 200 mile drive to visit family for the holiday. I managed to make it to my destination and, on my drive back, I contacted my local Ford dealer and was told to bring it in as soon as possible for evaluation. I pulled into the dealer service bay at 3 in the afternoon and was very happy that they were able to get the car in and fix the issue that day. The invoice stated, "Pulled codes, confirmed concern. Found corrosion in both wires going to the LR park brake actuator. Both wires broke clean in half. Replaced brake actuator pig tail.

Yesterday, 23 days later, I got the same error again. I brought the car back to the same dealer today. Different service reps working the desk today. They appeared to be almost as annoyed that I would show up without an appointment, as I was to have my 2 year old car suddenly inform me that it was unsafe to continue driving, twice in less than a month.

Some of you may recognize me from my only other posts on this forum regarding my HVB SOH, which at last check was 72%. This issue, to me is a much bigger concern. Even at 50% SOH, I would still get over 100 miles of driving range. With this issue, my range is effectively zero.

Frustrated.

 

[BillTinVT]

Update: Just picked the car up after the repair. Same thing as last time, but this time it was the right side. My advice to anyone else who has this issue in the future would be to ask to have both sides done if one side fails. BTW, my car is a 2023, so it was not included in the original CSP 22P31.

 

[JustSomeQuickGuy]

Update: Just picked the car up after the repair. Same thing as last time, but this time it was the right side. My advice to anyone else who has this issue in the future would be to ask to have both sides done if one side fails. BTW, my car is a 2023, so it was not included in the original CSP 22P31.

I wish I knew this was an issue on 2023's -- I would have had them do both. Instead, I'm waiting for the other one to go and another $500 bill.

Seems like @Ford Motor Company should cover this if it's going to continue to happen for all our cars.

 

[BillTinVT]

Here is. a pretty good video showing the park brake problem and how to fix it.

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