接着上次的AC问题，诊断有新进展， 用 MGS 读出如下：
Low side: zero pressure or vacuum; High side: very low pressure;
Service manual Diagnosis: Refrigerant does not circulate; refrigerant flow obstructed by moisture or dirt in system, or by gas leakage from expansion value.
Possible Remedy: Check expansion valve (EV); Clean out dirt in EV; Replace receiver; Evacuate air and charge new refrigerant to proper amount; Replace EV if gas leakage from expansion valve.
新问题: 这诊断可靠吗？ 怎么查 expansion valve gas leakage？最可能的root cause? 谢谢分享你的经验！
MGS reading picture:
