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Discussion Starter #1
I just picked up my 2005 LT in Palm Coast, Fl on Sunday. Rode it back to my daughters house in West Palm. 230 miles on about 3/4 of a tank. The mpg display was stuck on 16 all the way back. Every time I held down the BC button, the display would go to 200 and back to 16 as soon as I released the button. Any ideas on what is wrong.

Kudo's to Ron Miller for that fabulous Kontour seat. It was mid 80's and I was very comfortable, even with the seat heater accidently set to the low setting!

Now I just have to wait for Iowa to thaw out so I can ride hit home.
 

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Wrencher Extraordinaire
2005 K1200LT
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14,118 Posts
Chuck,


I do remember some one having this issue but for the life of me I cannot remember the cure. I'll try to flush out the gray matter and run that down for you.

It should jump to 200 at first then start counting up from 0 to some where around a reasonable number say 46 at a steady 60 MPH in 5th.
Gas guage is working OK?
 

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I'd suspect that one of two components of the MPG calculation is missing from the displpay processor - and it is most likely the fuel injector pulse length - assuming your odometer(s) work normally. They use the FI pulse lengths to get absolute fuel quantity measurements. (Which means that the FI rail pressure would directly affect the calibration of the MPG system)

(JZeiler) What lead to the display calculation is that? 16 mpg is probably as low as the reading can go.

I'm frankly just speculating based on my limited knowledge of how these things work. :wave
 

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Wrencher Extraordinaire
2005 K1200LT
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niel_petersen said:
(JZeiler) What lead to the display calculation is that? 16 mpg is probably as low as the reading can go.
You are probably right I never really notice the starting number after it drops from 200 (just assumed it was zero). 16 may very well be where it starts. I haven't found the post yet but there was one where a guy had the issue and fixed it.

Looking at the wiring there are three signals that leave the ECU and go to the instrument cluster (which contains the BC on the 05 + bikes). One is a temp light, one is common with the ignition coils and the third is a signal called TKVA. Could be that latter is missing.
 

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jzeiler said:
the third is a signal called TKVA. Could be that latter is missing.
I think that might be the one to look at. Does the OP know anyone with an oscilloscope? It could also drive the tachometer logic except I assume that is still working.
 
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