# Service bulletin 25PACF

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: 11027067
- Published by NHTSA: 2026\-01\-06
- Manufacturer's number: 25PACF
- Manufacturer's date: 2025\-12\-23
- Campaign id or software version: 25PACF
- NHTSA component: EXTERIOR LIGHTING

## NHTSA's summary

Parts and procedures are now available for all affected chassis equipped with Vehicle Electronic Control Unit \(VECU\) part number Q21\-1157\-013\-011 / Q21\-1157\-013\-013 / Q21\-1157\-002\-002 / Q21\-1157\-004\-004 / Q21\-1157\-006\-006 / Q21\-1157\-009\-009. See attached Parts Matrix for required parts per chassis.

## The document

- [NHTSA's copy of the document (PDF)](https://static.nhtsa.gov/odi/tsbs/2025/MC-11027067-0001.pdf)
- [If that address does not open, try this one](https://static.nhtsa.gov/odi/tsbs/2025/MC-11027067-9999.pdf)

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

## Components

Lighting

## Vehicles listed

- 2024 to 2026 KENWORTH L770
- 2023 to 2025 KENWORTH T180
- 2023 to 2026 KENWORTH T280
- 2023 to 2026 KENWORTH T380
- 2023 to 2026 KENWORTH T480
- 2023 to 2026 KENWORTH T680
- 2023 to 2026 KENWORTH T880
- 2023 to 2026 KENWORTH W990
- 2023 to 2026 PETERBILT 520
- 2023 to 2025 PETERBILT 535
- 2023 to 2026 PETERBILT 536
- 2023 to 2026 PETERBILT 537
- 2023 PETERBILT 548
- 2024 to 2026 PETERBILT 548
- 2023 to 2026 PETERBILT 567
- 2023 to 2026 PETERBILT 579
- 2024 to 2026 PETERBILT 589

## Recalls for the same vehicles and component

- [2025357](/recalls/tc/2025357.md), 2025-06-26: Lights And Instruments
- [25V436000](/recalls/nhtsa/25V436000.md), 2025-06-26: EXTERIOR LIGHTING:LIGHTING CONTROL MODULE:SOFTWARE
- [2025036](/recalls/tc/2025036.md), 2025-01-29: Lights And Instruments
- [25V041000](/recalls/nhtsa/25V041000.md), 2025-01-29: EXTERIOR LIGHTING:HAZARD FLASHING WARNING LIGHTS:SWITCH; ELECTRICAL SYSTEM: INSTRUMENT CLUSTER/PANEL; EXTERIOR LIGHTING:LIGHTING CONTROL MODULE:SOFTWARE
- [2022591](/recalls/tc/2022591.md), 2022-10-17: Lights And Instruments
- [2022314](/recalls/tc/2022314.md), 2022-06-15: Lights And Instruments

## Other bulletins for the same vehicles and component

- [34\-101](/bulletins/11033375.md), 2026-06-03, Service bulletin: EXTERIOR LIGHTING; ELECTRICAL SYSTEM. Certain Peterbilt Model 589 chassis equipped with LED headlamps may need a relay and fuses for the integrated heaters to be functional.
- [34\-100](/bulletins/11030934.md), 2026-04-07, Service campaign: EXTERIOR LIGHTING. Halogen Headlamp Operation \-Activating the Flash to Pass system on certain \[Kenworth / Peterbilt\] vehicles may cause one headlamp to deactivate.
- [25KWB/25PBB](/bulletins/11027057.md), 2026-01-06, Service bulletin: EXTERIOR LIGHTING; ELECTRICAL SYSTEM. A new Recommended Repair has been added. It must be used if safety recall 25PACF is performed prior to or at the same time as this repair since the 25PACF remedy also satisfies this safety recall.
- [25PACF](/bulletins/11022490.md), 2025-09-03, Service campaign: EXTERIOR LIGHTING. Procedures are now available for Phase 1 chassis equipped with Internal Combustion Engines \(ICE\) and Vehicle Electronic Control Unit \(VECU\) part number Q21\-1157\-013\-011 / Q21\-1157\-013\-013. Parts and procedures for Phase 2 chassis will be available at a later date. This bulletin will be updated at that time. Please refer to the condition section for more details. Certain Ethernet Multiplexed Architecture \(EMUX\) chassis fail to conform to Federal and Canada Motor Vehicle Safety Standards \(FMVSS/CMVSS\) No. 108. Delayed or unsteady illumination of the vehicle’s stop lamps, reverse lamps, turn signal lamps and inadvertent change in headlamp illumination or lift axle position may"
- [25PBB](/bulletins/11016628.md), 2025-04-04, Service bulletin: ELECTRICAL SYSTEM; EXTERIOR LIGHTING. Safety Recall The Exterior Lighting Switch \(ELS\) in certain Model 535, 536, 537, 548, and 567 chassis may not function and can be reset only by a key cycle. This issue may result in non\-compliance with FMVSS/CMVSS 101 and 108. Affected chassis must have the Vehicle Soft ware updated.
- [25KWB](/bulletins/11016469.md), 2025-04-04, Service bulletin: ELECTRICAL SYSTEM; EXTERIOR LIGHTING. Safety Recall Updated software and repair procedures are now available. The Exterior Lighting Switch \(ELS\) in certain T180/T280/T380/T480 chassis may not function and can be reset only by a key cycle. This issue may result in non\-compliance with FMVSS/CMVSS 101 and 108. Affected chassis must have the Vehicle Software updated.
- [25PBB](/bulletins/11014765.md), 2025-03-04, Other: EXTERIOR LIGHTING; ELECTRICAL SYSTEM. "Safety Recall – Interim Notification The Exterior Lighting Switch \(ELS\) in certain Model 535, 536, 537, 548, and 567 chassis may not function and can be reset only by a key cycle. This issue may result in non\-compliance with US Federal Motor Vehicle Safety Standards \(FMVSS\) or Canadian Motor Vehicle Safety Standards \(CMVSS\) 101 and 108. This bulletin will be updated when software and programming procedures are available."
- [25KWB](/bulletins/11014764.md), 2025-03-04, Other: EXTERIOR LIGHTING; ELECTRICAL SYSTEM. "Safety Recall – Interim Notification The Exterior Lighting Switch \(ELS\) in certain T180/T280/T380/T480 chassis may not function and can be reset only by a key cycle. This issue may result in non\-compliance with FMVSS/CMVSS 101 and 108. This bulletin will be updated when software and programming procedures are available."

JSON: [/v1/bulletins/11027067](/v1/bulletins/11027067)

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