Operation CHARM: Car repair manuals for everyone.

Warm-Up Cycle

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