NHTSA service bulletin

NHTSA Service Bulletin 629495: 2001, 2002 Chevrolet B7

Official manufacturer communication context for 2001, 2002 Chevrolet B7, with affected products, buyer checks and links into Carchieve recall, problem and VIN research.

NHTSA service bulletin 629495 summary graphic for 2001, 2002 Chevrolet B7
629495NHTSA document ID
Manufacturer communicationcommunication type
14affected product rows
75/100quality score

Reviewed June 2026 from NHTSA manufacturer communication and service bulletin records. Carchieve is independent and not affiliated with any vehicle manufacturer or government agency.

Quick answer

SUBJECT REGARDING REVISED DIAGNOSTIC TROUBLE CODE P1221 SERVICE MANUAL INFORMATION. *TT

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

MakeModelModel yearsBuyer note
ChevroletB72001, 2002Ask for service records and run the exact VIN before purchase.
ChevroletC Series2001, 2002Ask for service records and run the exact VIN before purchase.
ChevroletCorvette2001, 2002Ask for service records and run the exact VIN before purchase.
ChevroletExpress2001Ask for service records and run the exact VIN before purchase.
ChevroletSilverado2001Ask for service records and run the exact VIN before purchase.
ChevroletSilverado 35002001, 2002Ask for service records and run the exact VIN before purchase.
ChevroletSuburban2001Ask for service records and run the exact VIN before purchase.
ChevroletTahoe2001Ask for service records and run the exact VIN before purchase.
GMCB72001, 2002Ask for service records and run the exact VIN before purchase.
GMCC Series2001, 2002Ask for service records and run the exact VIN before purchase.
GMCSavana2001Ask for service records and run the exact VIN before purchase.
GMCSierra2001Ask for service records and run the exact VIN before purchase.
GMCSierra 35002001, 2002Ask for service records and run the exact VIN before purchase.
GMCYukon2001Ask for service records and run the exact VIN before purchase.

Buyer checklist

  1. Run the 17-character VIN and confirm the year, make, model, engine and equipment match the listing.
  2. Check recall campaign pages for safety actions that may require dealer repair.
  3. Compare this bulletin with common problem pages for the same model and component area.
  4. Ask the seller or dealer whether the bulletin procedure, update or inspection has already been completed.
  5. Use the used-car buying checklist and get an independent inspection.

Frequently asked questions

What is NHTSA service bulletin 629495?

SUBJECT REGARDING REVISED DIAGNOSTIC TROUBLE CODE P1221 SERVICE MANUAL INFORMATION. *TT

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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