Warm-Up Cycle

The powertrain control module (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 22° C (40° F) from the start-up temperature. 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.