Digital Information Module

I recently replaced the DIM (digital information module) on my 2003 Volvo XC70 Cross Country at 113500 miles. As you know the DIM has a message window that posts MPG, Average Speed, Miles left to and empty tank, etc. The average MPG before replacing the DIM was 20 +/- MPG city driving and 25 +/- MPG on the highway. The current MPG city driving is down to 15.5 MPG. I have questions:

  1. Does the DIM have to be readjusted somehow?
  2. How do I confirm it is the DIM? Do I reset the message window by driving a combo of city and highway driving or do I need to bring the car in for Oil/Filter change, which was recently done at 110,000 miles?
  3. I am currently monitoring the gas mileage for the next time at the pump, is this the right way to monitor the situation?

This is Garyhart I can be reached at 503 729 3522

@Garyhart…please remove your telephone number from your comment. This is a potentially dangerous thing to do on the internet.

This is Garyhart I can be reached at 503 xxx xxxx

The Jerky Boys will call you shortly.

This vehicle has a fuel economy rating of 16 MPG city, 15.5 isn’t bad for winter weather.

Yeah, kinda like saying my name is such and such and I live at such and such address in such and such city, and I’ll be gone for the next month, so feel free to ramsack my house and steal my car. Or I’m a single woman living alone and don’t know how to use a gun.