国标中对暖机循环的定义:
“3.11 暖机循环:指充分运转汽车,使得发动机冷却液温度比起动时至少升高22K,且至少达到343K(70℃)。”
英文:A Warm-up Cycle is defined as vehicle operation (after an engine off period) where the engine temperature rises from 40 °F (22 °C) to 160 °F (70 °C) after the vehicle was first started.
The PCM uses warm-up cycles as a counter to automatically erase a specific code and pertinent data from its memory when no faults (specific to the original problem) are detected within a specified number of warm-up cycles.
从定义可以推断出,暖机循环包括以下三点:
1、点火开关打开key on
2、冷却液升高22k
3、冷却液温度超过343k(70℃)
对此有几点疑问:
1、如果发动机冷却液升高,超过343k(70℃),但由于某种原因,冷却液温度降低低于343k(70℃),再次升高超过343k(70℃)时,是否算第二个暖机循环?