Diagnostic Procedure

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

Fig 1: DTCs P0601-P0607, P1600, P1621, P1627, P1680, P1681, P1683 & P2610: PCM Memory/Programming Malfunction

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