Batboard

I have a remote mounted mid power spectra with an A7 head. I t is be used with an HLN6432A plastic but when I switch it to an HLN6432B plastic I get a FL01/90 code. What is with the plastic that would cause the code. It has done it on both of my radios. Could some thing on the board have gone bad that I can not see?
Thanks
Steve

HLN6432B is the control housing rear and may be preventing the control cable from pluging in all the way.