Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la
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Warm-Up Cycle

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 raises 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.