A few decades ago when I worked on cars life was so simple. You had
a speedometer cable attached to a gear in the tranny, and if the
speedometer was wrong, you just changed the number of teeth on the
gear until you were happy with the result. That was then ...

Today I know that some cars use a Digital Ratio Adapter Controller
(DRAC) module to take readings from a sensor, apply some multiplier
value and then send the result on to yet another electronic brain
assembly which uses that value and then displays your speed in your
speedometer / odometer display.

There are even web sites on how you modify them to correct your
speedometer if it's wrong for no reason in particular, or because you
changed your tires / wheels in some non-standard way.

How does it work for Honda? What are the parts that do this
calculation?

-- CL.

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| Charles Lasitter | Mailing / Shipping |
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