Where is the odometer reading stored?

02V70 · Post by **02V70** » 04 Aug 2023, 13:35

When I first got my Volvo, the dash worked intermittently. When it didn't work, it acted as if it was completely unplugged, no lights, nothing on the screen, nothing. I think the dash started having the problem about 2 years before I fixed it. I was able to fix the dash by melting the solder points on the chips and some other electronic components on the inside of the dash. Could the not working dash have affected what the mileage on the car is, and making it show lower than it actually is? I read some reports of people's odometer being wrong when they replaced the dash. Is it possible to get a true reading from the ECU?

dikidera · Post by **dikidera** » 04 Aug 2023, 14:18

Yes the mileage is stored not just in the odometer, but also in a different module as a backup and also as a way to detect tampering. Which secondary module that is, is unknown to me.

Post by **scot850** » 04 Aug 2023, 17:22

On a P80 it is also stored on the ECU. Not sure if it is the same for the P2 cars.

Neil.

dikidera · Post by **dikidera** » 04 Aug 2023, 23:14

So I read the info is also stored in DDM and PDM as well, how true this is, someone can chime in.