LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Buick >> 2003 >> Century Base >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls Self-Diagnostics - 3.1L Engine >> Self-Diagnostic System >> Clearing Diagnostic Trouble Codes >> Warm-Up Cycles
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Warm-Up Cycles

The PCM uses warm-up cycles to run some diagnostics and to clear any Diagnostic Trouble Codes (DTCs). A warm-up cycle occurs when the engine coolant temperature increases 72°F (22°C) from the start-up temperature. The engine coolant must also achieve a minimum temperature of 160°F (71°C). The PCM counts the number of warm-up cycles in order to clear the Malfunction Indicator Light (MIL). The PCM will clear the DTCs when 40 consecutive warm-up cycles occur without a malfunction.