3.7

definitely annoying
Crashes / Fires:
0 / 0
Injuries / Deaths:
0 / 0
Average Mileage:
34,343 miles

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problem #29

Apr 272022

Mustang

  • miles
My break light switch pad is broken and is causing the car to not maintain speed and sluggish acceleration. I have seen other drivers report the same failure with their cars.

- Richmond, TX, USA

problem #28

Sep 202021

Mustang

  • miles
Traveling on highway using cruise control at posted speed limit. Approached slowdown due to accident and applied brakes. Accelerated to limit (manually) after passing accident. I was in middle lane. Vehicle abruptly began to decelerate. Continuous pressure on gas pedal did not increase speed, so I put on hazards and moved to slow lane. No failures on dashboard and quick scan through gages did not identify an issue. Re-applied pressure to gas pedal wanting to get to next exit. Car sped up, but when approaching 50 mph, it decreased again. Found that pumping gas would allow me to maintain highway speed. Pulled into truck stop at exit and turned car off. Message on console "Hill start assist not available". Let vehicle rest 15 minutes, added gas. Quick web search seemed to point to problem with ABS sensor. Seemed to drive ok in parking lot and road leading to highway ramp. Decided to try to get closer to home. Problem occurs immediately after climbing to 50 mph. Cruise control won't work. By carefully monitoring speed and pumping gas into overdrive when needed, I was able to get home. Could not get appointment with dealership until late afternoon next day. Hill start assist message comes on again when stopping. After arriving home and parking in garage I went inside for about 30 minutes. Needed to unload items from car and went back to garage noticing that the strip of lights above trunk are still on. Got back in car, started it (got hill assist message), turned lights on/off and turned off car. Now my rear brake lights are also on. I had seen a post about this, so unhooked battery to prevent drain. Next morning, reattached battery and had same problem. After more internet investigation, Awesome humans who have also had this dangerous issue and provided a $5 fix instead of a $500+ dealership fix. https://www.mustang6g.com/forums/threads/brake-light-switch-near-pedal-failure.122100/pag SUDDEN UNEXPECTED THROTTLE CAUSING SLOWDOWN ON BUSY INTERSTATE IS LIFE THREATENING.

- Dunwoody, GA, USA

problem #27

Jul 232021

Mustang

  • miles
Brake light switch pad broke, So the car thinks the brakes are on so it goes into "limp mode" and it starts turning off assist modes.

- Mobile, AL, USA

problem #26

Jul 202021

Mustang

  • miles
The issue is the Brake Light switch stop pad on the brake pedal which is a rubber type of plug. At 70,000 miles the brake light switch stop pad cracked and fell into floor board (see pictures). When that happened, the RPMs dropped to idle speed and the car slowed down. After a few seconds, the car would pick up speed again only to repeat the event over and over again. I understand that when the brake light switch stop pad is missing and the plunger on the switch is fully out, the car thinks that you are applying the brakes. I was lucky, I was on a two lane road with no traffic, but I was headed to an inter-state with heavy traffic. Ford (nor does anyone else) does not sell just the rubber plug which fits on the brake pedal, but it will sell the complete brake pedal assembly. Not sure the reason that the brake pedal would require the hole that requires the rubber plug, but think that Ford should be responsible for the replacement or a better solution for the repair (Provide a replacement plug, not just the complete Brake pedal assembly. Thank you for you time in this matter. [XXX] PARTS OF THIS DOCUMENT HAVE BEEN REDACTED TO PROTECT PERSONALLY IDENTIFIABLE INFORMATION PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6).

- Fortson, GA, USA

problem #25

Jul 202021

Mustang

  • miles
Brake pedal pad failed, causing car to suddenly brake even though brakes were not being applied. Ford Dealership recommended replacing brake light switch assembly. Brake lights stayed on even after the car was turned off. Had to disconnect the battery to prevent drain.

- Charlotte, NC, USA

problem #24

Jun 152021

Mustang

  • miles
Plastic clip for brake light switch disintegrates over time, causing reduced power and inoperative brake lights.

- Norfolk, VA, USA

problem #23

May 292021

Mustang

  • miles
The brake light switch function was inhibited due to the plastic retainer mounted on the pedal assembly. The plastic retainer had become brittle and caused it to come apart in pieces. The retainer acts a point of contact for the brake light switch plunger which signals to the ECM when the driver is applying or not applying the brakes. Symptoms of failure are constant illumination of rear brake lights with vehicle on or off. Disables cruise control. Also most importantly it limits throttle control by reducing throttle range spraticly. No driver warnings or lights are displayed or illuminated on the IPC. Problem has been verified and reproduced by independent service center.

- Chelsea, AL, USA

problem #22

May 112021

Mustang

  • 43,000 miles
A non-conductive pad is installed between the brake sensor switch and brake arm. The pad becomes brittle over time and breaks allowing the brake sensor to engage. This causes the car to go into 'limp' mode which can occur while driving on highways. This is a safety issue since it occurs randomly and can happen at high speeds.

- Sugar Land, TX, USA

problem #21

May 062021

Mustang

  • 80,000 miles
Break switch pad is really easy to break. Break lights stay on after car is stopped and in park and cut off. While driving very dangerous get no power to speed up and when you hit the gas nothing.

- Round Rock, TX, USA

problem #20

Apr 112021

Mustang

  • 120,000 miles
My battery died and required a jump the next morning. When I began driving, the car was throttling down as I was attempting to accelerate as if the engine was losing power. I didn't feel safe driving so I returned home and notice that my rear lights including the brake light stayed illuminated even when the car was off. I had to disconnect the battery in order to save my battery from draining again. After some investigating I found the brake switch pad was broken and this is what was causing the brake lights to be on all the time and causing the lack of engine power. This issue was not allowing the car to accelerate because the throttle is over-ridden by the brakes. The car was thinking the brake pedal was being pushed at the same time as the gas pedal. The brake switch pad breaking and causing this problem is very dangerous. I'm so lucky it happened on a local road and not the highway. I've read multiple accounts of this happening to other people. Ford needs to issue a recall and get this fixed to avoid major accidents.

- Flowery Branch, GA, USA

problem #19

Feb 282021

Mustang

  • 1,857 miles
The brake pedal stopper failed. The brake lights stay on all the time, you are unable to accelerate safely. This is a driveability and safety issue and poor design. This occured while driving on street, when I stopped is when I noticed the brake lights on after 15 minutes being stopped. I restarted car and attempted to accelerate but unable to effectively. I had a vehicle follow me around block and the brake lights were on all the time. Had vehicle trailered to the Ford dealer for diagnosis and repair. This vehicle has only 1857 miles on it.

- Gainesville, FL, USA

problem #18

Oct 302020

Mustang

  • 35,000 miles
Suddenly started experiencing a loss of power at highway speeds only remedied by slamming the accelerator to the floor which then caused the car to surge forward. After getting the car home also noticed the rear brake lights would remain on at all times. The twin problems ended up being connected. Turns out there is a small plastic/ceramic piece in the brake assembly that fails and breaks apart without warning - also no dashboard warnings after it fails. Causes the vehicle to think the brakes are being applied and cuts the power in response. This happened while traveling at interstate highway speed and was an immediate safety issue. Was told by the dealer this small part is very susceptible to Florida heat - unfortunately the whole brake assembly has to be replaced.

- N Venice, FL, USA

problem #17

Oct 022020

Mustang

  • 24,060 miles
Vehicle was sitting in driveway. My husband returned from an errand and noticed my vehicles brake lights were on would not turn off, even with the vehicle power off. I found broken plastic pieces on the driver side floorboard. When I researched the problem, results show this is a broken brake light switch pad. Missing this piece makes the brake lights remain on and the vehicle is unable to accelerate, creating a safety hazard.

- Spring, TX, USA

problem #16

Sep 092020

Mustang

  • 94,000 miles
The contact owns a 2015 Ford Mustang. The contact stated while driving 70 mph, the vehicle went into limp mode and the speed decelerated. The contact stated no warning light was illuminated. The contact parked on the side of the road to create a temporary fix to drive to the dealer. The vehicle was taken to autonation Ford mobile located at 901 East interstate 65 service rd S, mobile, al 36606, (251) 202-2016, where it was diagnosed with needing rubber grommet brake pedal to be replaced. The vehicle was not repaired. The manufacturer was informed of the failure. The failure mileage was approximately 94,000.

- Century, FL, USA

problem #15

Aug 162020

Mustang

  • 2,200 miles
The plastic brake light switch pad located on the brake pedal arm deteriorated and fell apart. After the pad was gone, the brake lights would not go out. It may also affect the traction control when the brake light switch stops working.this is a common problem after about five years. I noticed this defect right away, otherwise the battery would have gone dead. The specific part is not available from fors so they want you to replace the whole brake pedal assembly. The new one has the same defective part installed. This is a dangerous defect. It is also very expensive to repair.

- New Orlans, LA, USA

problem #14

Aug 112020

Mustang

  • 53,000 miles
There is a small pad on the brake pedal between the pedal shaft and the brake light activation switch. This pad shattered into small parts causing my brake lights to remain illuminated even when I wasn't braking. There was no warning provided by the car that the brake lights remained on. The lights were on when driving, when parked with the vehicle running or not running. I believe it broke while driving the vehicle but I can't be sure. There are multiple pads within the pedal cluster on the clutch and other pedals that are the same part and may be prone to failure. The attached photo includes the broken part and a picture indicating the empty spot where the part is missing.

- Greenwood, IN, USA

problem #13

Jun 072020

Mustang

  • 95,000 miles
Brake light stop pad broke into multiple pieces while driving, causing the brake light switch to malfunction. Brake lights remained on even when pedal is not depressed, which causes various performance issues due to the ECU believing the brake pedal is being depressed. Brake lights remained on when car was turned off.

- Mcgregor, TX, USA

problem #12

Jun 062020

Mustang

  • 50,000 miles
Break sensor pad broke causing lights to always stay on and car to be in limp home mode

- West Monroe, LA, USA

problem #11

May 302020

Mustang 4-cyl

  • 63,000 miles
While driving up a hill and attempting to pass another vehicle, I briefly lost acceleration. This happened again a few minutes later, and repeated a couple more times. I had never experienced this issue before and there were no warning indicators, or any other signs of mechanical failure. After happening several times, losing acceleration intermittently without taking my foot off the gas, a warning message displayed "hill assist not available, " and then disappeared. No other warning messages or dash indicators appeared, and I could not find anything relating to hill assist in my settings. After parking and shutting off my car, I noticed the brake lights remained on- I could not figure out how to turn them off. I searched all of these issues and found a blog post written by another owner experiencing the same issues. The other owner found small fragments of a broken plastic disc on the floor mat, below the petals- I found the same thing in my car. I went to a nearby auto zone for assistance and was advised the broken piece was a "brake light switch plunger." One of their associates quickly installed a $3 replacement for me, which seemed to fix all of the issues. I have not yet taken my car to Ford, but plan to do so asap. Each time I lost acceleration I was traveling up a hill, and it was only temporary- with no other systems appearing to be affected.

- Houston, TX, USA

problem #10

May 182020

Mustang 4-cyl

  • miles
The brake light switch plunger broke off the brake pedal causing the brake lights to constantly illuminate. This is a safety hazard for poor design substandard material.

- Corpus Christi, TX, USA

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