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Service bulletins for the 2026 Mack Pioneer

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.

100 on file from NHTSA, as of 2026-10-19.

By type

By component

By trouble code

By topic

Only bulletins with component: Electrical system are shown. Show all

Bulletins, newest first
CBR 2511-1 1020252025-11-03. Service bulletin. ELECTRICAL SYSTEM. CBR - Inverter Low/No Power Shutoff Bypass
CBR 2505 0920252025-10-01. Service bulletin. ELECTRICAL SYSTEM. The purpose of this CBR is to address the issue with Eco Roll disable switch notworking.
CBR 2502 0920252025-10-01. Service bulletin. ELECTRICAL SYSTEM. This CBR solution provides guidelines for ensuring the correct position of battery sensor modules and battery sensor harnesses on the Mack PR (4) and AN (4) chassis, as well as the Battery Sensor Diagnostic and Calibration Procedure.
CBR 2497 0920252025-10-01. Service bulletin. ELECTRICAL SYSTEM. Electronic control units on the VN(4), PR (4) and AN (4) contain information that is critical for vehicle functionality, maintaining vehicle life data, and maintaining vehicle compliance. Because of this, swapping ECUs from truck to truck even for diagnostic purposes may cause functional or compliance complications that may or may not be apparent.
CBR 2482 0920252025-10-01. Service bulletin. ELECTRICAL SYSTEM. Purpose of this CBR is to address Pop up message for PTO Malfunction when there is no PTO Installed.
CBR 2465 0920252025-10-01. Service bulletin. ELECTRICAL SYSTEM. This CBR pertains to two issues that may arise with the Proactive Engine Restart (Remote Engine Start System).
CBR 2491-1 0820252025-09-02. Service bulletin. ELECTRICAL SYSTEM. CBR - The purpose of this CBR is to provide instructions when fault code U300056: Electronic Control Unit, Invalid/Incompatible Configuration for the RCIOM is active.
CBR 2172-5 0820252025-09-02. Service bulletin. ELECTRICAL SYSTEM. CBR - When an OTA (Over-The-Air) job starts to program the VECU blocks the starter relay out, if the job ends in a Critical failure, the vehicle will remain in Safe State.

The summaries are NHTSA's. Each bulletin's page links NHTSA's copy of the manufacturer's document.