Lincoln bulletin SSM 54878
What it saysSome 2024-2026 Nautilus non-hybrid and 2025-2026 Aviator vehicles equipped with 28 radio speakers (minor feature code IDBBN) and 2025-2026 Navigator vehicles may exhibit a no audio/sound condition with no communication… NHTSA’s full summary ↓
Lincoln filed this with NHTSA as a service bulletin dated May 27, 2026, received Jun 3, 2026, about the electrical system. It names 7 model years (2024–2026). A service bulletin is not a safety recall: it is the manufacturer telling its dealers how to diagnose or repair a condition, and whether the work is paid for depends on the warranty in force. Quoting the number at a service desk can save a diagnosis.
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What the bulletin says
Source: NHTSA's summary of the manufacturer's communicationWhat it applies to, as the document itself states it — the build window in the manufacturer’s own words, read by machine from the PDF NHTSA serves. The build date is on the certification label in the driver’s door jamb; the dealer settles a borderline vehicle by its VIN.
Some 2024-2026 Nautilus non-hybrid and 2025-2026 Aviator vehicles equipped with 28 radio speakers (minor feature code IDBBN) and 2025-2026 Navigator vehicles may exhibit a no audio/sound condition with no communication with the audio digital signal processing module (DSP) with U0238 stored in the audio control module (ACM). This may be due to the DSP. To determine if the DSP is the root cause, remove the DSP fuse from the battery junction box (BCMC fuse F40 for Aviator, BCMC fuse F138 for Nautilus, BJB fuse F5 for Navigator). Inspect the fuse for an open and make sure the fuse has proper blade contact. After one minute, reinstall the good fuse. If the concern is still present or a fuse concern is found, refer to Workshop Manual (WSM), Section 415-00 for normal diagnostics. If communication has been re-established with the DSP, install a new DSP ordered from Ford Component Sales using the On-Line 1878 form to correct this condition. Refer to Workshop Manual (WSM), Section 415-00. For claiming, use causal part 18B849 and labor operations 12651D and 12651D13.
Trouble codes it names: U0238
Document filed under this number
| Document | Kind | Dated | NHTSA id | At NHTSA |
|---|---|---|---|---|
| SSM 54878 | Service bulletin | May 27, 2026 | 11033258 | PDF, 74 KB |
The summary is NHTSA’s abstract of the document, as filed under 49 CFR 579.5. One communication is usually filed as several documents — the bulletin, a dealer notice, an owner letter — and the number on any of them finds this page. A PDF link is shown only once NHTSA’s own server has been seen to serve that document; the rest are checked over the following nights. Quote the number at a service desk; it is what the dealer’s system is keyed on.
Model years it names
Source: as the manufacturer filed themA vehicle page’s bulletin list shows the newest few communications filed against that model year; the count there is every one.
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What owners reported
Source: NHTSA complaint databaseOwners of the 7 model years this bulletin names have filed 107 complaints with NHTSA since 2015. 19 of them name Electrical System — the same broad component group this bulletin is filed under. NHTSA groups complaints coarsely, so that means the same area of the vehicle, not necessarily the same fault.
This vehicle has been returned to service 5 times. It is currently in service for the same 4 issues that it was taken to service for the very first time on 12/10/2025. This includes inappropriate braking on the interstate, driver window malfunction, the key intermittently stops working, and the connectivity does not regularly work.
2025 Lincoln Navigator · Electrical System · filed with NHTSA Feb 2, 2026
During a short drive between and roughly 27 miles, the red battery light on the dash display illuminated just as we were turning into the Holiday/Circle K gas station in . No other warnings or messages appeared on the dash, and upon restart after returning to the vehicle, the red battery light did not reappear.
2025 Lincoln Nautilus · Electrical System · filed with NHTSA Aug 28, 2026
Multiple loss of power, misfires, rough running and abnormal shifting. These events have put my family and I at risk as well as posing a significant risk to other drivers sharing the road due to the sudden loss of power while on the highway. Lincoln is dismissive and not taking this seriously.
2025 Lincoln Aviator · Electrical System · filed with NHTSA Sep 15, 2026
A complaint is one owner’s account, not a defect finding, and a bulletin is not a recall. Nothing here says this bulletin was issued because of these complaints, or that the repair it describes fixed them. Complaint files on this site begin in 2015.
More bulletins about the electrical system
Source: same model, same component group187 other manufacturer communications filed against these Lincoln models under the same component group (electrical system), newest first. The eight newest are listed; the rest are on the Lincoln list.
| Number | Kind | Dated | NHTSA’s summary |
|---|---|---|---|
| SSM 55208 | Service bulletin | Sep 25, 2026 | Some 2024-2026 F-150, 2025 Explorer/Aviator, 2025-2026 Expedition/Navigator, or 2026 F-Super Duty vehicles may exhibit diagnostic trouble co… |
| SSM 55198 | Service bulletin | Sep 24, 2026 | Some 2025-2027 Navigator vehicles equipped with multi-contour seats (minor feature code BYBAL) may exhibit a condition where the second-row… |
| IPMA-26.11.0 | Over-the-air update | Sep 16, 2026 | Quality improvements include: -Image Processing Module A update to the latest software level |
| SSM 55172 | Service bulletin | Sep 15, 2026 | Some 2025 Aviator/Explorer/Police Interceptor Utility vehicles may exhibit a "Steering Assist Fault Service Required" message and diagnostic… |
| TSB 26-2358 V2 | Service bulletin | Sep 11, 2026 | Some of the vehicles listed in the Model statement above equipped with one-touch up/down windows may exhibit a condition where a window does… |
| BCM-26.DC | Over-the-air update | Sep 4, 2026 | Quality improvements include: - Enables the Open On Approach feature |
| 26B19 | Other | Aug 31, 2026 | Recommended Repair Prior to Sale Customer Satisfaction Program 26B19 2024-2025 MY Nautilus 2.0L Hybrid Vehicles Powertrain Control Module… |
| TSB 26-2395 | Service bulletin | Aug 26, 2026 | This article supersedes 26-2287. Reason for update: update the labor operation numbers to add MT to operations C, F, G, H, J, K, L and M, an… |
Quote the number at the service desk. It is what the dealer’s system is keyed on.
Every manufacturer communication NHTSA holds for Lincoln, by the number printed on the letter.
Common questions
Source: NHTSA, 49 CFR 579.5Is Lincoln SSM 54878 a recall?
No. A service bulletin is a manufacturer communication filed with NHTSA under 49 CFR 579.5; a safety recall carries an NHTSA campaign number (two digits, a letter, six digits) and a federal duty to repair for free. Check the vehicle’s recalls by VIN at nhtsa.gov/recalls, or on its page here.
Is the SSM 54878 repair free?
Not automatically. A service bulletin describes how to diagnose or repair a condition; who pays depends on the warranty in force, any extension, and the dealer. Quoting the number can save a diagnosis either way.
Which vehicles does SSM 54878 cover?
The manufacturer filed it against 7 model years: 2026 Lincoln Aviator, 2025 Lincoln Aviator, 2026 Lincoln Nautilus, 2025 Lincoln Nautilus, 2024 Lincoln Nautilus, 2026 Lincoln Navigator and more. Whether one particular vehicle is affected is a matter of its VIN and its build, not its model year alone. The document itself sets the build window: built on or before 23 Mar 2026 — the build date is on the certification label in the driver’s door jamb.