P27B4 on Ford vehicles

A model year is listed because the code is named in its own record — a bulletin filed against it, or an owner’s complaint about it — not because every one of these vehicles sets it. Counts are documents in NHTSA’s files, not failure rates.

Owners’ own words, scrubbed of anything identifying. Unverified reports filed with NHTSA — what was said, not a finding that it was true.

Bulletins and campaigns Ford filed with NHTSA whose summary names P27B4. Quote the document number at the service desk — it is a diagnosis the maker has already written down.

• TSB-20-2063 Service bulletin
  2020-03-05 · Electrical System
• Some 2020 F-Super Duty vehicles equipped with a 6.7L engine built on or before 5-Feb-2020 may exhibit an illuminated malfunction indicator lamp (MIL) with diagnostic trouble codes (DTC) P203B, P2201 and/or DTC P27B4 stored in the powertrain control module (PCM). The vehicle may also exhibit a forced idle condition. This may be due to various strategies within the PCM software. To correct the condi
• TSB 20-2074 Service bulletin
  2020-03-12 · Power Train
• Some 2020 F-Super Duty vehicles equipped with a 6.2L/7.3L gas engine and 10R140 transmission built on or before 5-Dec-2019 may exhibit an illuminated malfunction indicator lamp (MIL) with diagnostic trouble code (DTC) P27B4 stored in the powertrain control module (PCM). This may be due to various strategies within the PCM software. To correct the condition, follow the Service Procedure to reprogra
• TSB 20-2336 Service bulletin
  2020-09-22 · Engine And Engine Cooling
• Some 2020 F-Super Duty vehicles equipped with a 6.7L engine built on or before 19-Aug-2020 may exhibit an illuminated malfunction indicator lamp (MIL) with diagnostic trouble codes (DTC) P0300-P0308, P0603, P203B, P208B, P208C, P2201, P24C2, P27B4, P07F6 and/or P27B5 stored in the powertrain control module (PCM). The vehicle may also exhibit a forced idle condition. This may be due to various stra
• TSB 25-2343 Service bulletin
  2025-07-25 · Fuel/Propulsion System
• This article supersedes TSB 22-2491 to update labor times from M-time to AP-time and add a cap. Some of the vehicle listed in the model statement above may exhibit at least one of the following conditions: - Illuminated red triangle with diagnostic trouble code (DTC) P27B4 stored in the secondary on-board diagnostic module C (SOBDMC) - Charge Status Indicator (CSI) is blinking red with DTC P0A7F s

A stored code names the test that failed, never the part that caused it. The record above is what Ford and its owners have filed about it; the code’s page across every make has the whole file.