1:https://www.google.ca/search?q=how+to+test+car+a%2Fc+relay&oq=test+a%2Fc+relay&%7Bgoogle:searchFieldtrialParameter%7D%7Bgoogle:searchClient%7D%7Bgoogle:sourceId%7D%7Bgoogle:omniboxStartMarginParameter%7Die=UTF-8 2:直接換relay,DIY是有風險滴。