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JBD and Bavarian Technic Cable Diagnostic / Reset Tool

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CAN I RESET MY SPEEDOMETER to measure the correct SPEED with this BT tool?

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I have been reading about the subject tool to help diagnose and reset error when you install a new battery. I also read where you can reset lighting quality, turn things on/off...etc with this tool. If that is so, ie. am i able to reset my speedometer to MEASURE THE CORRECT SPEED?

SEveral years ago, i wrote BMW (Munich) a real nasty-gram stating that my speedometer was measuring +5 mph faster than what I was going...and it was a pain in the not know exactly what I was doing. I said that I found it deplorable that BMW German engineers could measure machine tolerances down to the a gnat's ass...but failed to set a speedometer to measure correct speed. In the meantime to getting a response to that letter, I continued my www research for the better explanation. I came across an article that talked about a dinkbat lady was stopped for speeding in her BMW, got ticketed, and had to pay an enormous fine, but she contended her speedometer was off. So she sued BMW and lo and behold, she won, so BMW decided to recalibrate all speedometers to measure...+5 mph (9-10 km/hr) more than the car was actually going.

And as it happens, the Fed'l DOT didn't have a problem with that since most people do +5 over the speed with the speedometer measuring high, in fact, the drivers were now DOING THE SPEED LIMIT. Then.. I took my car into the local dealership complaining about how it was "OFF". and when they checked it, they said the voltages and amperages were all within tolerance. Then i got my response form BMW Munich that pushed my letter to BMW North America. BWM NA send me a letter that stated they were aware of this but since the speedometer did not measure speed in excess of what the car was traveling, it was OK.

So..with this little story in your hip pocket, CAN I RESET MY SPEEDOMETER to measure the correct SPEED with this BT tool?
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The only way you can correct the bias that BMW puts there is to go into the ECU with a correction box and dial it in. If you do a Google search there was a guy with a full write up doing this and willing to sell the correction box to those interested. Other than that you are not going to be able to code your way through making that correction...
Thanks. . Figured as much. Reminds me of Apple Computers where you have no control over things....b/c "Apple Knows Best !" That said, is the BT Tool worth getting ?
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