Diagnostic Procedures

WARNING: This page is about a different car, the 2003 GMC Envoy XL and 2003 Chevrolet TrailBlazer. However, it is still accessible from the selected car via links, so may be relevant.

Fig 1: DTC P2121 (Steps 1-9)

Courtesy of GENERAL MOTORS CORP.

Fig 2: DTC P2121 (Steps 10-19)

Courtesy of GENERAL MOTORS CORP.