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P1870 on the 1996 Chevrolet Blazer

The bulletins listed name this code in NHTSA's summary, or are about the same components. A bulletin or a recall listed here may apply to the model year. None of it is a diagnosis.

This code is specific to a manufacturer and is not described here. Its meaning is in the manufacturer's service information.

Bulletins for this model year that name P1870
9774L60E08A1997-08-14. Service bulletin. AUTOMATIC TRANSMISSION 1-2 AND/OR 2-3 UPSHIFT SLIP/FLARE, NO 3RD OR 4TH GEAR, DTC P1870, LAUNCH SHUDDER (REVISE VCM WIRING). *TW

1 on file from NHTSA, as of 2026-10-19. See them in the bulletin list. A bulletin lists model years: read the document for which vehicles it concerns.