The mileage is stored in the instrument cluster which it sounds like the cluster has gone bad and needs to be replaced here is a video to help you see what you are in for when doing the job and diagrams below to show you on your car.
https://youtu.be/_HEC44xENxw
Removal and Installation
NOTE: If installing a new instrument cluster, it is necessary to upload the instrument cluster configuration information to the diagnostic tool.
Depower the supplemental restraint system (SRS).
NOTE: The instrument cluster finish panel is held in place with retaining clips that are attached to the bezel.
Remove the instrument cluster finish panel.
Remove the 4 screws and the instrument cluster.
Disconnect the electrical connector.
To install, reverse the removal procedure.
If a new instrument cluster was installed, download the instrument cluster configuration information from the diagnostic tool into the new instrument cluster.
Image (Click to make bigger)
Monday, May 16th, 2011 AT 9:57 PM
