题目内容：

英语翻译
A产品的所有型号一共使用4种底盘.其中有2种底盘的型号是经常影响通过率的.
因为此2个型号,PCB焊接点只有2个,所以在测试的时候不是很好固定.
（ps,下面说的不要翻译,A指一个系列产品,A里面只要分几个大类的型号,然后这些型号产品的底盘一共有4中,这段话比较别扭,：） ）

优质解答

There are four kinds of chassises of Product A.The passing rate is affected by two of them.So there are only two types of Product A were passable.There are only 2 PCB wiped joint on the board,it's hard to fix when testing