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Eisboch[_8_]

"iBoaterer" wrote in message
...

In article ,
says...

But, at least I know the gas gauge and the speedometer readings are
correct.

Now you should see if the speedometer reads correctly as well, don't
want a ticket! Just go 60 mph (96.56kph). It should take one minute to
go one mile.

----------------------------------------------

Did that. It reads fine So does the trip odometer. It's only the
total mileage odometer that reads crazy.

I am getting to the bottom of this, only because it has me very
curious.
There are two plastic gears buried in the instrument cluster. The
gears apparently rotate mini tachometers that send pulses to the BSM
computer which in turn calculates the mileage displays.

One gear (the smaller of the two) is for the trip odometer which
reads in tenths of kilometers. The larger gear is for the total
mileage odometer which reads whole kilometers only.

My guess is that the gears are fine, simply because both displays
increase in readings while driving. The problem has to be either with
whatever the tach unit is (generating too many pulses) or some
component in the computer itself that is counting too many pulses.

This is about as far as I'll take this investigation. I have no
desire to rip apart the instrument cluster or replace the BSM
computer. Car only cost $2,500.
I really don't care if the mileage reading is correct or not as long
as the speedometer and gas gauges are working, which they are.

BTW ... I've found several cautious on car forums that you should
never "reset" the trip odometer while the car is in motion. It should
only be reset while parked or stopped. Apparently the design of the
odometer/trip odometer system that is in the Saturn is common to those
in cars of many manufacturers.
The small, plastic gear is prone to being stripped if you reset the
reading while it is spinning.