Affected vehicles are equipped with a single exhaust system. In the affected vehicles, the rear axle wiring harness bundle may contact the rear axle housing.
Damaged electric parking brake wiring may lead to inadvertent parking brake application while driving, potentially resulting in loss of control of the vehicle and increasing the risk of a crash.
In certain circumstances, the rear axle wiring harness bundle may contact the rear axle housing.
Over time, contact with the rear axle housing can cause the abrasion-resistant tape and circuit insulation of the wiring harness assembly to wear, exposing the wiring.
The driver may see a parking brake warning light and a message on the instrument panel cluster.
Owners will be notified by mail and instructed to take their vehicle to a Ford or Lincoln dealer to have the rear axle wiring harness inspected.
If the abrasion tape that covers the wire bundle exhibits wear-through, the suspect harness will be replaced with a new service harness. If the abrasion tape does not exhibit wear-through, the dealer will install a protective tie strap and tape wrap. There will be no charge for this service, according to Ford.
Ford provided the general reimbursement plan for the cost of remedies paid for by vehicle owners prior to notification of a safety recall in May 2023. The ending date for reimbursement eligibility is estimated to be September 11, 2024.
History of Ford's Recall
On February 23, 2023, Ford's Critical Concern Review Group (CCRG) opened an investigation into reports describing unintended parking brake application on 2021 model year F-150 vehicles. The warranty and field reports indicated damage to the wiring containing the rear electric parking brake circuits.
Initial investigation determined that the damaged wiring is part of a rear axle wiring harness assembly that contains wires for the rear electric parking brakes and other electrical components. The rear axle wiring harness bundle may contact the rear axle housing which can, in certain circumstances, result in chafing of the wiring harness bundle.
Further investigation determined that, over time, the chafing of the rear axle wiring harness assembly can wear through the abrasion-resistant tape and circuit insulation, ultimately exposing copper wiring which can result in the grounding of circuits on the rear axle housing. This abrasion can be expedited due to corrosion on the rear axle housing.
From May through July 2023, Ford Engineering performed vehicle-level testing and data analysis to determine the effect on vehicle operation of damaged circuits within the wiring harness bundle. The investigation found that vehicles may experience an unintended activation of the electric parking brake if the low-side electric parking brake motor circuit is shorted to the ground.
As of July 11, 2023, Ford said it is aware of 918 warranty and three field reports for the wire chafing condition in North America, received within the range of August 2021 and July 2023.
Of these reports, 299 indicated that the electric parking brake had unintended activation, of which nineteen (19) allege electric parking brake application while driving.
Ford added that it is not aware of any reports of accidents or injuries related to this condition.
On July 14, 2023, Ford's Field Review Committee reviewed the concern and approved a field action.
Originally posted on Automotive Fleet