2021 Ford F-150: ABS light or ABS activating

Filed Sep 11, 2026 · Brakes · GA

ABS Control module and brake booster assembly failed. Vehicle would not crank or start. Disconnected battery negative pole for one minute to reset PCM. Vehicle started. Drove immediately to independent service center without difficulty. Service center confirmed vehicle no start the next morning. Found several DTC codes including U3001 (Control Module Improper Shutdown) U300A (Ignition switch) U0121 (Lost communication with ABS) U0554 (Invalid Data recieved from Accessory Protocol Interface) and U0415 (Invalid Data Received from ABS) Flowchart determined ABS module is bad. Anti Lock Brake System control module failed which rendered the system inoperative. Warning on dash that Anti Lock Brake System failed was prominent among other warnings. (Traction Control, Service Needed, Door Ajar (was closed), Hood ajar (was closed) Assembly was replaced and ABS module reprogrammed by independent service center. They retained the bad assembly.

Filed Jan 26, 2026 · Transmission · 35,000 miles · MI

The contact owns a 2021 Ford F-150. The contact stated that while driving at an undisclosed speed, the ABS, Advancetrac, and several unknown warning lights illuminated. The vehicle was taken to the dealer, where it was confirmed that the failure was due to an unrepaired recall. The contact was informed that parts were on back order. The vehicle was not repaired. The contact received notification of the federal safety agency Campaign Number: 23V896000 (Power Train). Additionally, the contact stated that the parts had been on back order since January 2025. The manufacturer was made aware of the failure, and a case was filed. The failure mileage was approximately 35,000.

Filed Sep 12, 2025 · TX

My truck will not update its internal software that controls everything from windows to ABS braking system. My truck has numerous pending updates, verified by my dealer and FMCO update section, that are not being sent to my truck. The updates are there for a reason, to improve and to prevent issues. I asked my dealer to do them, they said it would cost $1500 to do it since they would not install over the air as they should. I contacted Ford on 9/12/25 and they refused to assist by either paying the dealer and or by using my Ford ESP warranty. My safety is at risk because these updates address transmission issues, braking issues, electical issues etc all that could fail and cause an accident. Add these failure to update with the exisisting fuel pump problem and the truck is a serious problem . I am told by Ford that my updates are "stuck" and that there is nothing that they can assist with and I must take to a dealer and pay for the updates that others get for free. But, should there ever be a "recall" for my trucks failure to update, I can apply for a refund. I have about 12 different updates that will not download to my truck. In the history of the truck, this is not the first time it would not download updates. Shortly after it was built it was taken to Ford and a "forced update for the Bluecruise technology" had to be done. Critical software updates to the trucks main computer that do not initiate is not acceptable and a danger to this truck! Thank You!

Filed Sep 10, 2025 · Transmission · 45,000 miles · KS

The contact owns a 2021 Ford F-150. The contact stated that there was an abnormal squeaking sound coming from the vehicle while driving at various speeds. The failure persisted, and the ABS, Hill Start Assist Not Available, Pre-Collision Assist Not Available, and several other messages appeared on the instrument panel. The vehicle was taken to a dealer where the contact was informed that the wheel hub bolt in the rear axle was fractured and caused the failure. The contact was informed that the VIN was included in the federal safety agency Campaign Number: 23V896000 (Power Train); however, the part to do the recall repair was on backorder. The manufacturer was notified of the failure and requested a status update on the part. The contact was then informed that the dealer would call the manufacturer and request the part to repair the vehicle. The vehicle was not repaired. The failure mileage was approximately 45,000.

Filed Apr 14, 2025 · Brakes · 45,000 miles · NY

The contact owns a 2021 Ford F-150. The contact stated while driving at various speeds, the vehicle suddenly decelerated and could only be driven at an excessively slow speed. The traction control, brakes, and ABS warning lights were illuminated. The vehicle was towed to Kings Auto, where it was diagnosed that the ABS pump had failed and needed to be replaced. The mechanic related the failure to the federal safety agency Campaign Number: 21V533000 (Service Brakes, Hydraulic). The vehicle was not repaired. The dealer was notified of the failure and informed the contact that the VIN was not included in the recall. The manufacturer was contacted and referred the contact to the federal safety agency Hotline for assistance. The failure mileage was approximately 45,000.

Filed Sep 27, 2024 · Brakes, Driver assistance · CA

Since 09/23/2024 my 2021 ford f150 the ABS ,service advance trac and pre-collition assist not available messages are displayed every time i press the brakes, the truck is only 3 years and has 21077 miles

Filed Sep 21, 2024 · Brakes, Driver assistance · UT

I was slowing to a stop at a stoplight in traffic when the brake pedal dropped to the floor and the truck was no longer slowing. The ABS, Anti collision, and check brake system lights all illuminated. I was able to slow the truck and place in park to stop. Vehicle was taken to dealership where it was found to be in perfect condition according to the mechanic. I have been told that I should have no issue taking the vehicle although nothing has been resolved.

Filed May 29, 2024 · Brakes, Driver assistance · MD

Unknown which component is failing. It started with a rumble while accelerating or coasting but goes away when I shift into neutral so I believe that is the transmission. Other issues that are occurring randomly, speedometer will change indication to slower speed than I am actually going or it will drop to 0 while I am driving. Alerts and faults that have shown at the same time the speedometer goes out are: Powertrain fault, ABS, Forward Collision Warning, Parking Collision Warning, Automatic Emergency Braking, Lane Departure Warning, Blind Spot Warning, Lane Keeping Assistance, Cross Traffic Warning. Also a random metallic spinning noise coming from under the truck. It has been in the dealer garage 5 times now.

Filed May 8, 2024 · Electrical · 66,000 miles · TX

The contact owns a 2021 Ford F-150. The contact stated that while driving at an undisclosed speed and braking, several safety features disabled independently. The contact stated that the Pre-Collision Assist, ABS, and other unknown warning lights were illuminated. The contact stated that the failure occurred often. The vehicle was not diagnosed or repaired by an independent mechanic or dealer. The manufacturer was made aware of the failure and opened a case. The failure mileage was approximately 66,000.

Filed Apr 5, 2024 · Brakes · 28,000 miles · OK

The contact owns a 2021 Ford F-150. The contact stated that the brake power booster was emitting a hissing sound when the brake pedal was being depressed. The contact used an excessive amount of pressure to depress the brake pedal. The ABS warning light was illuminated but deactivated independently. The vehicle was taken to the dealer, but the cause of the failure was not determined. The dealer confirmed that the failure was related to the federal safety agency Campaign Number: 21V533000 (Service Brakes, Hydraulic) however, the VIN was not included. The vehicle had not been repaired. The manufacturer was made aware of the failure, and it was confirmed that the VIN was not included in the recall. The contact was referred to the federal safety agency Hotline to file a complaint. The failure mileage was 28,000.

Filed Jan 29, 2024 · Brakes · 54,500 miles · IN

The contact owns a 2021 Ford F-150. The contact stated while driving approximately 30 MPH, the rear brakes were engaged, and the brake warning light illuminated. The "ABS Function-Limited" message was displayed. The contact called the local dealer and was informed that there was no recall or warranty coverage for the failure. The manufacturer was contacted and referred the contact to the federal safety agency Hotline for assistance. The failure mileage was approximately 54,500.

Filed Dec 26, 2022 · Brakes · PA

Brake failure, brake pedal went to floor had to firmly stand on peddle rear wheels eventually locked up and truck skidded to stop. warning lamps that lit up are check brake system, hill start assist not available, service advance trac, pre collision assist not available, ABS and brake light was illuminated. very dangerous situation. This is the second time this happened the first was September 2021 they replaced the brake booster at 7,000 miles this occurred again 12/25/2022.