{"nhtsa_id":629487,"type":"service_bulletin","type_name":"Service bulletin","date_added":"2002-04-02","date":"2002-02-01","document_id":"020604005","mfr_campaign":null,"replaces":null,"component":"ELECTRICAL SYSTEM:IGNITION:MODULE","mfr_system":null,"summary":"SUBJECT REGARDING REVISED DIAGNOSTIC TROUBLE CODE P1221 SERVIC EMANUAL UDPATE. *TT","document":null,"url":"https://open.wenmarpro.com/bulletins/629487","components":[{"id":"electrical","name":"Electrical system","parent":null},{"id":"ignition","name":"Ignition","parent":"electrical"}],"codes":["P1221"],"topics":[],"vehicles":[{"make":"CHEVROLET","model":"CORVETTE","year_from":2001,"year_to":2002,"match":"exact","vehicle_ids":["2001_chevrolet_corvette","2002_chevrolet_corvette"]},{"make":"CHEVROLET","model":"SILVERADO","year_from":2001,"year_to":2001,"match":"exact","vehicle_ids":["2001_chevrolet_silverado"]},{"make":"CHEVROLET","model":"SUBURBAN","year_from":2001,"year_to":2001,"match":"exact","vehicle_ids":["2001_chevrolet_suburban"]}],"as_of":"2026-10-19","note":"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.","attribution":[]}