SSM 2023–2026 Super Duty "Trailer Disconnected" Message — 55239

[Ford Tremor Forum]

Special Service Message · SSM 55239

This is a Special Service Message, not a recall. SSMs are informational notes Ford sends dealers about a known condition or a change in procedure. They are not repair orders, and they don't by themselves change what is covered.

Published: Oct 12, 2026
Applies to: F-250, F-350 (2023–2026 model years)

Restrictions stated in the source:

• Build dates: built on or before 08-May-2026
• Equipment: equipped with a trailer brake control module / equipped with electric over hydraulic brakes

Also listed in the source (outside this forum's coverage): F-450 SD 2023–2026, F-550 SD 2023–2026

Summary (official text)​

Some 2023-2026 F-Super Duty vehicles equipped with a trailer brake control module and built on or before 08-May-2026 may exhibit a "Trailer Disconnected" message after cycling the ignition off and back on with a trailer connected. This may be due to the presence of an integrated battery charger on a trailer equipped with electric over hydraulic brakes. If trailer functionality is restored after unplugging and plugging the trailer connector back in while the ignition is on, this condition can be corrected by downloading and performing the "Trailer Brake Configuration" application using the latest software version of the Ford Diagnosis and Repair System (FDRS) scan tool. For claiming, use causal part 19H332 and labor operations 12651D and 12651D4. Workshop Manual (WSM), Section 417-01 Exterior Lighting > Diagnosis and Testing > Trailer Lamps > Pinpoint Test G •The Message Center Displays A False Trailer Disconnected Message When A Trailer Is Connected To The Vehicle - Only For Electric Over Hydraulic (EOH) Equipped Trailers When Vehicle Trailer Brake Type Setting Is Set To Electric Over Hydraulic• has bee

Sources​

• SSM 55239 (PDF, NHTSA document 11038444) — Oct 12, 2026

Details from NHTSA as of Oct 14, 2026. If NHTSA or Ford revises this notice, this post is updated and significant changes are noted in a reply. The linked documents are the authority, and a dealer can confirm whether it applies to your VIN.

Have you experienced this issue with your truck? Let us know your model year and engine, plus any diagnosis or repair details.

 

[The Evil Twin]

Another “Trailer Disconnected” problem?

 

[donmatteo]

Another “Trailer Disconnected” problem?

You don't get that message if you don't tow.

Think smarter not harder

 

[xrocket21]

I have got this, pain in the butt.

 

[The Evil Twin]

You don't get that message if you don't tow.

Think smarter not harder

But I do tow, and have never seen such message

 

[Toxophilite]

Thank you for posting - Seems like this is primarily associated to trailers with an integrated battery charger.

 

[HBTFD]

I get this error randomly using the 4 prong connectors, 3 different trailers. I do not use the 7 prong.
2024 tremor XLT 7.3.

 

[MVI]

I had this with 7 pin trailers. My truck was at ford for about 30 days, and I had four different F150 loaners.

They got it fixed, finally and said that was the beginning of the Tech Documentation that became SSM 55239