Volvo: 1994 Volvo 940 Wagon Questions, 1994 volvo 940, volvo 940 wagon

Question
I have a few questions to ask about my 1994 Volvo 940 Station Wagon.  I currently have just over 365,000 miles driven on it.

For one, my odometer reads about 5 miles for every 1 mile actually driven.  Just out of curiosity, what is causing this?  My speedometer also does not work.  

My break lights do not work also.  I tried replacing the bulbs, but that did not fix the problem.  The brake light on the rear door works when I brake, but not the ones on the rear of the car.  Also, after replacing them, now my right rear blinker goes on steadily when I apply the brake, then turns off after I release the brake pedal.  If I try to turn on the right blinker without applying the break, it sporadically blinks, but with the brake pedal being pushed AND the right blinker on, it blinks correctly.  My question is how to make my brake lights work again, and how to make the right blinker not light up when I simply apply the brakes.  And how to make my right blinker work correctly again.

I hope these questions make sense to you.  Thank you in advance for your time!

Chelsea

Answer
Chelsea,
Speedo has an internal fault and will need to be removed for testing. There is no cable it has an electrical pick up in the rear axle.
There might be some poor contacts at the rear light assemblies or the bulb out relay has failed. Trace the power from the brake light switch to see where it stops. Look carefully at the light assembly to see if the wires are tight and all bulb sockets are in place and tight.