I have a 2012 Dyna Switchback that the speedometer all of a sudden indicates the wrong Range, A and B mileage readings.The bike starts and runs good. Has a 1 year old battery that has been load tested good also.I have disconnected the battery for a few days and when reconnected get the same problem. I can reset the A and B to zero and they stay at zero for just a few minutes and then both go to 781.3 miles???? I have unplugged both the BCM and the ECM modules and sprayed all the contacts with contact cleaner. The A and B readings change from zero to 781.3 whether the engine is running or not and the Range goes to some incorrect reading. I have taken the grounds loose and cleaned them and retightened them. Does the ECM or the BCM control the speedometer readings??? Can the BCM and ECM units be swapped out for other used units ??? Anyone got any ideas?? Thanks

 

Any codes?

 

No codes.

 

Your speedo is on the risers? There is a plug and wires on the bottom of the speedo that leads back to the main wiring harness. Check for loose pins,corrosion etc.on both ends.
When you turn the run switch on while holding the trip meter reset, does the needle sweep up and back down?
Does the speedo read consistently while riding or does it jump around?

 

Thanks joe40x. The Switchbacks speedometers are located on the gas tank but I'm sure there is still a plug and wires connections that I can check. Have not done so yet, but I will. The speedometer needle does sweep up and back to check for codes as it should. Also, the speed does appear to be accurate while riding and does not jump around. Odd thing is that both the A and B always jumps to the same reading (781.3) after staying on 0 for a minute or so with just the ignition switch on. Thanks again.