There are two sections where this could be enabled from; one is correct one--the other not so much. The two sections are the J1708 and the RV-C. You most likely added these in the RV-C. Try using the J1708 side instead.
After speaking with Mark (uber-nerd) he's leaning this direction. Give us a call if some clarification or additional help is needed.
Hello Da141 The early computer (program) within your DD will either produce the codes or, they won't. Not to sound ambiguous--the final PROM upgrade for DDEC II is v154. Prior versions i.e. 141 were almost as good, and anything prior to that may not produce odometer readings. Version-154 is needed for full functionality. A replacement PROM (for that updated program) can be had pretty easily. Here is that prom as a bolt-on module: http://www.ebay.com/itm/Detroit-Diesel-R6171618-EPROM-Stabilizer-Kit-/301130020850 ~$55 delivered. With that you can connect your new Silverleaf unit using a complete setup which we supply. The basic VMSpc with cables and software are $395 plus postage. A fella or gal who can replace a tail lamp or change the oil in a car can usually install one of these without more than a coffee or smoke break. That basic unit uses a USB connection to your Windows Laptop or Windows Tablet. All Windows Operating Systems (OS) are supported. WiFi and Bluetooth (wireless) connections are supported for Windows systems prior to Windows-8. To marry the two (Laptop and VMS unit) a small amount of software is installed. Then shazaam; you're ready to go.