NHTSA Service Bulletin 10174986: 2020 Western Star 4700
Official manufacturer communication context for 2020 Western Star 4700, with affected products, buyer checks and links into Carchieve recall, problem and VIN research.
Reviewed June 2026 from NHTSA manufacturer communication and service bulletin records. Carchieve is independent and not affiliated with any vehicle manufacturer or government agency.
Revision for Service Bulletin for Western Star 4700/5700 Pana-Pacific 540 Radio Controls Not Operating Normally. This bulletin replaces the version dated 03/25/2020. Pana-Pacific DEA540 radios (A22-74389-000, A22-77161-000) may cease to respond to volume control settings from the steering wheel switches or the controls on the radio faceplate, resulting in erratic volume control. This bulletin replaces the version dated March 26, 2020.The procedure to check the current software version of the radio is updated.
What this bulletin may mean before buying
Treat this as service research, not a verdict on one car. Before you buy, compare this communication with official recall campaigns, model-level owner complaint patterns, and the exact vehicle’s VIN-decoded specifications. A bulletin can help you ask a seller or dealer sharper questions about software updates, known repairs, warranty extensions and service history.
Affected products listed in this communication
Buyer checklist
- Run the 17-character VIN and confirm the year, make, model, engine and equipment match the listing.
- Check recall campaign pages for safety actions that may require dealer repair.
- Compare this bulletin with common problem pages for the same model and component area.
- Ask the seller or dealer whether the bulletin procedure, update or inspection has already been completed.
- Use the used-car buying checklist and get an independent inspection.
Frequently asked questions
What is NHTSA service bulletin 10174986?
Revision for Service Bulletin for Western Star 4700/5700 Pana-Pacific 540 Radio Controls Not Operating Normally. This bulletin replaces the version dated 03/25/2020. Pana-Pacific DEA540 radios (A22-74389-000, A22-77161-000) may cease to respond to volume control settings from the steering wheel switches or the controls on the radio faceplate, resulting in erratic volume control. This bulletin replaces the version.
Is a service bulletin the same as a recall?
No. A recall is a safety campaign with a required remedy for affected VINs. A service bulletin or manufacturer communication usually describes diagnostic, repair, software, warranty or service information.
How should a used-car buyer use this bulletin?
Use it as a research signal. Compare it with recalls, owner complaints, service records, a VIN report and an independent inspection before buying.
Check the exact VIN before you buy
Model-level pages show public safety patterns. A full VIN report helps confirm the exact vehicle, decoded specs, recall applicability and buyer checks.
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