1999 C5 convertible.

Can somebody please help me determine what might be causing the following codes.

U1016- loss of communication with PCM
U1040- loss of communication with TCS
U1064- loss of communication with BCM
U1088- loss of communication with SDM
U1096- loss of communication with IPC
U1160 Loss of Communications with LDCM
U1255 Serial Data Line Malfunction
U1301 Serial Data Line Short to Voltage

My guess would be that the serial line data problem might be causing
the communication loss problems.
I get the infamous service traction control, service ABS, service ride control everytime I start the car. I bought the car three months ago and the problem started the day after. It was intermitent at first but now is constant. However once in a while I'll start the car and have no messages. My gut feeling is the problem might be rain related as we have had a lot of rain as of late.
One other problem I've had two or three times is I will get all the above messages and also reduce power, shocks inoperalbe, the A/C shuts down and I have no power to the drivers door controls. If I shut off the car, open the door, and shake the boot protecting the wiring harness I regain power to the door controls and the messages goes away whe I restart the car. This problem also seems to be rain related.

Any help at all will sure be appreciated. Thanks

 

you mite get more help from the c5 section