Service bulletin 21N08

A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.

The communication, as NHTSA indexes it (as of 2026-10-19)
Type	Service bulletin
NHTSA id	10201668
Published by NHTSA	2021-09-30
Manufacturer's number	21N08
Manufacturer's date	2021-09-13
NHTSA component	ELECTRICAL SYSTEM

NHTSA's summary

Certain 2017-2020 Model Year F-150, 2018-2020 Expedition, and 2018-2020 Navigator Vehicles Equipped with a 3.5L GTDI Engine PCM Reprogram Due to Engine Shudder ;In a very low percentage of the affected vehicles, an engine shudder may develop after receiving the PCM update provided in program 21B10. For peace of mind, Ford is providing a no-cost, one-time repair for customers who receive the PCM update under program 21B10 to revert the PCM calibration back to its original state before program 21B10.

The document

The document is the manufacturer's. This site does not hold it. NHTSA files a document at one of these two addresses; we have not asked NHTSA which.

Components

Electrical system

Vehicles listed
FORD EXPEDITION	2018, 2019, 2020
FORD F-150	2017, 2018, 2019, 2020
LINCOLN NAVIGATOR	2018, 2019, 2020

Listing a model year does not mean every vehicle of it is concerned: the document says which.

Recalls for the same vehicles and component
26V372000	2026-06-09. ELECTRICAL SYSTEM: INSTRUMENT CLUSTER/PANEL
26V370000	2026-06-09. ELECTRICAL SYSTEM: INSTRUMENT CLUSTER/PANEL
25V886000	2025-12-18. ELECTRICAL SYSTEM: INSTRUMENT CLUSTER/PANEL
25V346000	2025-05-23. ELECTRICAL SYSTEM:BODY CONTROL MODULE:SOFTWARE
2022257	2022-05-17. Electrical
20V467000	2020-08-10. ELECTRICAL SYSTEM:STARTER ASSEMBLY
20V263000	2020-05-08. ELECTRICAL SYSTEM: INSTRUMENT CLUSTER/PANEL; POWER TRAIN:AUTOMATIC TRANSMISSION:GEAR POSITION INDICATION (PRNDL)
20V262000	2020-05-08. FORWARD COLLISION AVOIDANCE: AUTOMATIC EMERGENCY BRAKING; FORWARD COLLISION AVOIDANCE; ELECTRICAL SYSTEM: INSTRUMENT CLUSTER/PANEL
2020023	2020-01-23. Electrical
2019568	2019-11-12. Electrical

A recall listed here may apply to some of the same vehicles. Only the manufacturer can say whether it applies to one vehicle.

Other bulletins for the same vehicles and component
25E10-S1	2026-10-02. Other. 25E10-S1 Owner letter
25E10-S1	2026-08-03. Emissions. NEW VEHICLE DELIVERY HOLD - Emissions Recall 25E10 - Supplement #1 Certain 2018-2020 Model Year F-150 Vehicles With 3.3L Engines and 2016-2019 Model Year Explorer, Taurus, and Flex Vehicles With 3.5L Engines Powertrain Control Module (PCM) Reprogramming
SSM 55037	2026-07-27. Service bulletin. Some 2018-2024 Expedition and 2018-2027 Navigator vehicles equipped with a rear seat entertainment system/Lincoln Play may experience various system concerns. Rear seat entertainment systems are not on a controller area network (CAN) and are not supported by the Ford Diagnostic and Repair System (FDRS). Certain system concerns may be resolved through software updates which will automatically download once each individual monitor is connected to Wi-Fi. Diagnostic support for rear seat entertainment systems is provided by VOXX electronics. If necessary, contact the VOXX Customer Service Department at 1-866-869-7888. If possible, record the device serial number by selecting the gear/Setup icon > Settings > Device and Software > About. If the unit will not power up, the serial number is on a label on the back of the monitor. It is helpful to know the date the issue occurred, how long the monitors were on prior to the issue, what app/input/media was being used, and if the system software was recently updated prior to the concern starting. For claiming, refer to the Warranty and Policy manual for
25H05 S1	2026-04-30. Other. Harvest Program 25H05 – Supplement #1 Certain 2011-2021 Model Year Vehicles Software Verification Harvest Program
SSM 54720	2026-04-10. Service bulletin. Various 2020-2026 Ford and Lincoln vehicles equipped with blind spot information system (BLIS) may experience an inoperative blind spot monitoring with a "Blind Spot System Fault" message displayed in the instrument panel cluster (IPC). This may also be accompanied by diagnostic trouble codes (DTCs) B118C:11 and/or B118C:15 stored in the driver door module (DDM), and/or B118D:11 and/or B118D:15 stored in the passenger door module (PDM). This may be due to the wiring connector from the mirror to the BLIS module. If diagnostics lead to an internal mirror wiring harness fault, a new lower level BLIS light pigtail is now released for service. It is not necessary to replace the exterior mirror assembly. Use part number SC3Z-14A411-B to resolve the concern.
SSM 54589	2026-03-04. Other. Some 2019-2024 Ford and Lincoln vehicles equipped with SYNC3 may experience various connectivity concerns with The Ford App Lincoln App including but not limited to: missing activation prompt pop-upon the vehicle's center display screen when attempting to activate vehicle through The Ford App Lincoln App, incorrect location global positioning system GPS reported through The Ford App Lincoln App, problems with remote commands being performed through The Ford App Lincoln App and or incorrect data information reported on The Ford App Lincoln App. These symptoms will be accompanied by diagnostic trouble code DTC B156D 89 in the TCU. This may be due to the accessory protocol interface module APIM software. To correct the condition, update the APIM software.
SSM 54601	2026-02-27. Service bulletin. Ford and Lincoln vehicles equipped with wired keyless entry keypad systems and accessory wireless keyless entry keypad systems may or may not come with a wallet card containing the master code. Unlike the integrated wired keypad, the accessory wireless keypad master code cannot be retrieved from the vehicle using a diagnostic scan tool or from the label printed on the body control module (BCM). The Factory Keyless Entry Code application within the diagnostic scan tool will not provide an applicable master code for the accessory wireless keypad. If the wallet card for an accessory keypad is not available, the "Wireless RF Keypad Diagnosis Guide" can be referenced and provides direction on how to retrieve the master code. This guide is located under the Workshop Manual tab > Accessories > Installation > Wireless RF Keypad Diagnosis Guide > PPT C > Step C2.<br /><br /> Note: The only available keypad for some vehicles from the assembly plant is the accessory wireless keyless entry keypad. The integrated wired keypad cannot be installed on vehicles not equipped from the factory with a wired keyless entry k
SSM 54555	2026-02-12. Service bulletin. Some 2020-2022-Corsair, 2021-2023 Nautilus, 2020-2024 Navigator/Aviator, and 2021-2024 Mustang Mach-E vehicles equipped with phone-as-a-key may exhibit various phone-as-a-key concerns with diagnostic trouble codes (DTC) U200D:15, U200E:15, U200F:15, B1589:31/49 through B1598:31/49, B1A56:31/49, B1D55:31/49, and/or B15A5:56 stored in the remote function actuator (RFA) module. If any of these DTCs are detected during diagnostics, clear the DTCs, reprogram the RFA to the latest software level and start a new Ford Diagnosis and Repair System (FDRS) session. Verify that DTCs are no longer present. If only the B1589:31/49 through B1598:31/49, B1A56:31/49, B1D55:31/49, and/or B15A5:56 DTCs return in the RFA after a self-test, follow normal Workshop Manual (WSM) diagnostics in Section 419-01. Repair as necessary outside of this article. For claiming, use causal part 14G617 and labor operations 12651D and 12651D4.
25H05	2025-12-03. Other. This is a proactive investigation program by Ford Motor Company to inspect a limited number of affected vehicles that are customer-owned. Ford is voluntarily conducting this program to evaluate the software currently installed on one or more electronic modules in the affected vehicles.
TSB 25-2570	2025-12-01. Service bulletin. This article supersedes TSB 24-2165 to update the TSB Service Procedure. Some vehicles listed in the Model statement above may exhibit various SYNC performance related concerns including but not limited to: Display operation concerns Navigation inoperative Voice recognition concerns Phone connection issues Dropped phone connections Applink related performance Travel Link not present or showing incorrect traffic Slow system response NOTE: Ford has found some of the APIMs replaced and returned for inspection contained an outdated software level and the APIM did not require replacement. The customer concern may have been resolved by updating the APIM with latest level of software. The SYNC 3 universal thumb drive will be able to update the APIM software without the use of a scan tool and does not require the process to be monitored. Ford will be monitoring APIM replacements to confirm TSB directed software updates have been performed.