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Service bulletins for the 2020 Chevrolet 4500HD

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.

383 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
22-NA-1152022-06-06. Service bulletin. ENGINE AND ENGINE COOLING; ELECTRICAL SYSTEM. This service bulletin provides information for U.S. dealers ONLY to refer to the Battery Maintenance Report to identify vehicles in dealer inventory that require attention.
22NA0122022-05-31. Service bulletin. ELECTRICAL SYSTEM:ADAS:PARKING ASSIST:SENSORS. This service bulletin provides information for dealers/technicians on Stone Chip/Membrane Damage, Broken Connector and/or Sensor Retaining Tabs, and/or Paint Damage of Park Assist Sensors.
21-NA-1152022-04-06. Service bulletin. ENGINE AND ENGINE COOLING; EQUIPMENT; ELECTRICAL SYSTEM. This informational bulletin provides information for dealers/technicians on Available ECM Calibration to Activate High Idle Mode for Fleet Vehicles.
20NA1322021-12-20. Service bulletin. ELECTRICAL SYSTEM:12V/24V/48V BATTERY. This warranty administration bulletin provides policy information on the requirements for battery testing and warranty replacements.
21NA1242021-07-06. Service bulletin. ELECTRICAL SYSTEM. This service bulletin provides diagnostic tips/steps on testing for possible EVAP leaks in the system to correct a customer concern of an MIL Illuminated with DTCs P0442 and/or P0455 Set.
21NA0202021-05-24. Service bulletin. BACK OVER PREVENTION; ELECTRICAL SYSTEM. This technical bulletin provides a procedure to correct a click type noise heard from the starter when cranking.
21NA0612021-05-10. Service bulletin. ELECTRICAL SYSTEM:IGNITION:ANTI-THEFT:IMMOBILIZER/PROXIMITY:KEY/SENDER. This service bulletin provides information for dealers on Using EL-52545 When Diagnosing PEPs Transmitter Key Fobs (North America ONLY).
20NA1322021-05-03. Service bulletin. ELECTRICAL SYSTEM. This warranty administration bulletin provides policy information on the requirements for battery testing and warranty replacements.
16NA0192021-02-01. Service bulletin. POWER TRAIN; ELECTRICAL SYSTEM:SOFTWARE. This informational bulletin provides information on Transmission Adaptive Functions and Correcting Low Mileage Harsh Shifts, Slips, or Flares.
20NA1502020-08-31. Service bulletin. ELECTRICAL SYSTEM. This technical bulletin provides repair information to correct a customer concern of Glow Plug Control Module Update for P133x and/or P067x.
20NA1322020-08-10. Service bulletin. ELECTRICAL SYSTEM. This warranty administration bulletin provides policy information on the requirements for battery testing and warranty replacements.
060089029T2020-06-22. Service bulletin. ELECTRICAL SYSTEM: INSTRUMENT CLUSTER/PANEL; EQUIPMENT. This informational bulletin includes information on Interior Cleaning - Instrument Panel (IP), Hard or Plastic Surfaces, Seats, Carpet, Leather, Vinyl, Fabric Cleaner, Stain Remover, Restorer - Product Availability.
060089029S2020-06-22. Service bulletin. ELECTRICAL SYSTEM: INSTRUMENT CLUSTER/PANEL; EQUIPMENT. This informational bulletin includes information on Interior Cleaning - Instrument Panel (IP), Hard or Plastic Surfaces, Seats, Carpet, Leather, Vinyl, Fabric Cleaner, Stain Remover, Restorer - Product Availability.

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