I have a 2007 Hyundai Sonata SE XM (153K miles). The speedometer and odometer have quit working completely. The speedometer doesn’t even move from zero, no bouncing around or anything. The odometer also is not logging miles. My transmission shifts gears just fine and the cruise control works as well. I bought an OBD-II scanner and no codes came up. My first thought was maybe the vehicle speed sensor, but everything I’ve found on that say the car will shift poorly and the speedometer bounces around. Thanks for your help!
Not true about the speedometer bouncing around. It may bounce around for a few seconds, minutes or even days before dropping to zero, but a failed VSS will can cause a total zero on the speedo and odo and the transmission will shift just fine. I can’t explain the cruise control though as I have never tried using that on a car with a failed VSS.
This makes me suspect the gauge cluster itself or the power to the gauges. Start with the fuse panel and look for a fuse that feeds the gauges. BTW, do the dash lights work when you turn on the headlights. Does the dim/bright control work for the dash lights?
Vehicle speed sensor would be my first guess. Maybe this will help. Not sure if your VSS is in the same place, but it is an easy swap. http://aaronlevie.blogspot.com/2008/06/sonata-vehicle-speed-sensor.html
My vote is for the speed sensor. A couple of years ago the speed sensor on one of my cars failed which led to no cruise, no speedometer, and a flashing OD light.
There were no codes present on that one either.
If the transmission is shifting okey and the cruise control works the VSS is most likely producing a signel. You can measure that that the connection plug with a DVM.
The VSS signel is processed by the speedometer head in a lot of cases. The signel is amplified/ squared up with a Schmidt trigger flip flop; and drives the speedometer stepper motor. If something is jambing the gear train the motor won’t turn. So check the trip mileage counter – reset it a couple of times. Otherwise it probably is a gearing jamb in the odometer but it could be an electronic problem. You might run this by a speedometer calibration shop for troubleshooting and/or repair.
Hope this helps.