DIY Odometer Reprogramming

A simple instructional video illustrating how to program your digital car odometer using simple electronics, a computer with a serial port, some soldering knowledge and an understanding of hexi-decimal programming.

Most vehicles store their digital odometer reading on the instrument cluster on a re-writable EEPROM chip. Once the chip is located, it can be de-soldered from the board and connected to a computer's serial port where its data can be downloaded and manipulated. This will work for most vehicles that store the odometer reading in the cluster itself as opposed to the ECU.

The data on the chip is coded in inverted hex values. Through experimentation, a pattern was observed that related the values to the digits on the odometer's digital display. The data is then edited and rewritten to the chip, which is then soldered to the odometer board and put back into the car.