CAN communication fault diagnosis method

The invention relates to a CAN communication fault diagnosis method which comprises the following steps: performing system initialization; judging a first type of faults, quitting in case of the firsttype of faults, or else executing a next step; establishing a fault diagnosis enabling condition module; judging a second type of faults if the first type of faults do not happen and an enabling state En is equal to 1. Through the steps, the first type of faults, that is, completely interrupted communication, and the second type of faults, that is, alternatively connected and interpreted communication, can be recognized, then corresponding fault disposal can be taken directly if the first type of faults happen, in addition, the second type of faults can be judged when the first type of faultsdo not happen, fault priorities are classified, repeated judgment can be avoided, the diagnosis efficiency is greatly improved, and convenience can be brought to later fault checking. 本发明涉特别涉及种CAN通信故障诊断方法，包括如下步骤：系统初始化；进行第类故障的