Volvo: 1999 c70, electrical issues, speed signal

Question
I own a C70 that recently has begun to have some electrical issues.  The speedometer sometimes stops working.  Once this happens the flashing arrow light, abs light and brake light come on and stay on until the speedometer works again on its own. It also shifts slowly when going from a stop position when the speedometer does not work.  Any advice.

Answer
Tom,
It might be missing a signal from the speed sensor in the trans. Have the codes read and see if there are any faults that need correcting. I have also seen the ABS control unit that often goes bad cause a speedo failure. That ABS unit goes bad often. No speed signal and the ABS and speedo along with the trans get bad signals and set fault codes.