# Service bulletin TSB 20\-2074

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.

- Type: Service bulletin
- NHTSA id: 10172964
- Published by NHTSA: 2020\-04\-02
- Manufacturer's number: TSB 20\-2074
- Manufacturer's date: 2020\-03\-12
- NHTSA component: ELECTRICAL SYSTEM; POWER TRAIN

## NHTSA's summary

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 reprogram the PCM.

## The document

- [NHTSA's copy of the document (PDF)](https://static.nhtsa.gov/odi/tsbs/2020/MC-10172964-0001.pdf)
- [If that address does not open, try this one](https://static.nhtsa.gov/odi/tsbs/2020/MC-10172964-9999.pdf)

The document is the manufacturer's. This site does not hold it.

## Components

Electrical system, Transmission and driveline

## Trouble codes named

P27B4

## Vehicles listed

- 2020 FORD F\-250 SD
- 2020 FORD F\-350 SD
- 2020 FORD F\-450 SD
- 2020 FORD F\-550 SD

## Recalls for the same vehicles and component

- [2022193](/recalls/tc/2022193.md), 2022-04-14: Powertrain
- [22V256000](/recalls/nhtsa/22V256000.md), 2022-04-14: POWER TRAIN:AUTOMATIC TRANSMISSION
- [2022074](/recalls/tc/2022074.md), 2022-02-17: Powertrain
- [22V087000](/recalls/nhtsa/22V087000.md), 2022-02-16: STRUCTURE:FRAME AND MEMBERS:UNDERBODY SHIELDS; POWER TRAIN:DRIVELINE:DRIVESHAFT
- [2021437](/recalls/tc/2021437.md), 2021-07-16: Powertrain
- [21V536000](/recalls/nhtsa/21V536000.md), 2021-07-15: POWER TRAIN:AXLE ASSEMBLY
- [20V365000](/recalls/nhtsa/20V365000.md), 2020-06-23: POWER TRAIN:AUTOMATIC TRANSMISSION:TORQUE CONVERTER; POWER TRAIN:AUTOMATIC TRANSMISSION
- [20V099000](/recalls/nhtsa/20V099000.md), 2020-02-21: POWER TRAIN:DRIVELINE:DIFFERENTIAL UNIT; POWER TRAIN:DRIVELINE:DRIVESHAFT

## Other bulletins for the same vehicles and component

- [SSM 55218](/bulletins/11038166.md), 2026-10-06, Service bulletin: POWER TRAIN; UNKNOWN OR OTHER. For 20202026 vehicles equipped with the 10R140 transmission, a new Transmission Clutch Circuit Leak Test has been introduced in the Ford Diagnosis and Repair System \(FDRS\). This test utilizes the pressure and vacuum transducer \(PVT\) when available. Workshop Manual \(WSM\) updates related to this diagnostic procedure are planned for release in Q4 2026. The new test improves the accuracy of detecting leaks within transmission fluid circuits and replaces the previous air check method. The previous air check procedure has been shown to produce a high rate of false positives, which may lead to unnecessary repairs when no actual leak is present. Accordingly, the air check procedure is not to be used for diagnosing internal transmission hydraulic leaks or as justification for transmission replacement.
- [TSB 26\-2088 v2](/bulletins/11037979.md), 2026-10-05, Service bulletin: UNKNOWN OR OTHER; POWER TRAIN. This bulletin supersedes 24\-2249. Reason for update: update the claim quantity of the torque converter nuts, part number and claim quantity of the front support assembly bolt washers, and part number change of the fluid pan from the Parts List. Reissued 01\-Oct\-2026 \- Added LC3Z\-7G091\-B to the part list
- [TSB 26\-2216](/bulletins/11032694.md), 2026-05-14, Service bulletin: POWER TRAIN. This bulletin supersedes 25\-2549. Reason for update: To add 2020 model year chassis cab vehicles. Some of the vehicles listed in the Model statement above may exhibit an incorrectly illuminated malfunction indicator lamp \(MIL\) with diagnostic trouble codes \(DTC\) P0420 and/or P0430 stored in the powertrain control module \(PCM\). This may be due to the software in the PCM. This condition does not affect vehicle drivability or durability.
- [SSM 54720](/bulletins/11031263.md), 2026-04-10, Service bulletin: ELECTRICAL SYSTEM; LANE DEPARTURE: BLIND SPOT DETECTION. 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.
- [TSB 26\-2088](/bulletins/11029923.md), 2026-03-10, Service bulletin: POWER TRAIN. This article supersedes TSB 24\-2249 to update the claim quantity of the torque converter nuts, part number and claim quantity of the front support assembly bolt washers, and part number change of the fluid pan from the Parts List. Some of the vehicles listed in the Model statement above may exhibit a harsh reverse to drive engagements with no diagnostic trouble codes \(DTC\). This may be due to sticking valves in the main control valve body and/or damaged input shaft seals \(F9\), and the output shaft seals \(F10\). Additional model information: Built On Or Before 13\-Dec\-2021 10R140 Automatic Transmission
- [25N10](/bulletins/11029724.md), 2026-03-05, Other: POWER TRAIN; UNKNOWN OR OTHER. Certain 2017\-2025 F\-450 – F\-600 Super Duty Chassis Cab Upfitted with an Aerial Bucket Frame Rail Crack
- [SSM 54589](/bulletins/11029595.md), 2026-03-04, Other: ELECTRICAL SYSTEM. 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 54592](/bulletins/11029081.md), 2026-02-27, Service bulletin: POWER TRAIN. For 20172026 vehicles equipped with a 10R transmission, a revision to the Road Testing Vehicle procedure has been made in the WSM, located in Section 307\-01 \> Diagnosis and Testing. This updated procedure improves the diagnosis of customer reported transmission concerns and aids in locating the proper root cause. During diagnosis and testing, details regarding whether the condition is more prevalent when the vehicle is hot or cold, throttle percentage at the time of occurrence, vehicle speed, the specific shift involved, and whether the issue occurs during transmission engagements \(N\>R, N\>D, R\>D, or D\>R\) should be noted. Engineering requests including these detailed operating conditions that will significantly assist with root cause analysis. Diagnosis, testing, and repair should use established labor times outside this article.
- [SSM 54601](/bulletins/11029052.md), 2026-02-27, Service bulletin: ELECTRICAL SYSTEM; STRUCTURE:BODY; UNKNOWN OR OTHER. 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
- [TSB 25\-2572](/bulletins/11025854.md), 2025-12-01, Service bulletin: POWER TRAIN; ENGINE. This article supersedes TSB 25\-2322 to update the Service Procedure, Labor Operations and Parts List. Some of the vehicles listed in the Model statement above may exhibit an upper engine ticking or tapping noise at idle. Customers may also report experiencing rough engine performance, engine misfire, or a malfunction indicator lamp \(MIL\) with diagnostic trouble code \(DTC\) P0301\-P0308 in the powertrain control module \(PCM\). This may be due to camshaft and/or valve tappet having excess wear within the engine assembly.

JSON: [/v1/bulletins/10172964](/v1/bulletins/10172964)

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