Speedometer intermittently functions
 

My speedometer over the past couple weeks intermittently functions. Sometimes I start the car and the speedo works. Other times I start the car and it doesn't work. There's no in between, meaning once I start the car and start to drive, if the speedo was working to begin with it stays working.
Did some reading and it seems the speedo is connected to the ABS module? Not sure how. When I turn the ignition key to the II position there is no ABS light so I'm thinking the module is bad.
My plan is to just replace the ABS module via www.midwest-abs.com which will hopefully solve both problems. Thoughts?

in my 2000 c70 the ABS module is badd and the speedo comes and goes.

Hoping thats it. Mt ABS light comes on and off too...

...m

What year is your 850?

97 850 na
Also, it's just the speedo that's going out. the RPMs will work as do the turn signals, etc.