Looks like a firmware upgrade is available (for 50 bucks). I'm running 3.17mb version i think. This might possibly explain why the HP may not work.
Firmware Details: Ample Outdoors
Versions 3.0 to 3.14 - Base ScanGauge features were in place, minor technical changes were made to prepare for X-Gauge release.
Version 3.15 - (2007) X-Gauge functionality added.
Version 3.16 - (~2009) AVG and TFC X-Gauges included in firmware.
Version 3.17 - (2009) Minor bugfix release for the Gallons/Litres to Empty X-Gauge, sometimes the word Gallons or Litres would flash across the Gauge screen on some vehicles.
Version 3.17mb - (05/2010) Minor bugfix release for some vehicles that use the KWPF protocol (particularly vehicles that used a Mercedes Benz engine) Fixes a timing issue that prevented the SGII connecting to some KWPF vehicles.
Version 4.02 - (04/2011) Major release. Changes to menu system and setup options. Turbo Boost gauge and Horsepower gauge added as standard gauges. Performance Monitor added - record, save and playback up to 8 performance runs. Revisions to Trouble Code clearing protocols. Fuel consumption can now be displayed in kilometres per litre or Litres per 100 km. Alternate method for clearing DTCs. Horsepower gauge adjustment. Changes to the on screen Menu structure. For more information feel free to download the latest user manual for the new v4.02 ScanGauge2 here.(10.6mb)
Version 4.05 - (07/2011) Addition to the Performance Monitor that allows a performance run to be recorded in metric as well as imperial units.
Version 4.06 - (09/2011) Re-introduction of the Mercedes Benz fix that was added to 3.17mb. The fix was mistakenly left out of 4.02 and 4.05 and is only of benefit to a small number of early model Mercedes Benz vehicles that use the KWPF protocol.
Firmware Details: Ample Outdoors
Versions 3.0 to 3.14 - Base ScanGauge features were in place, minor technical changes were made to prepare for X-Gauge release.
Version 3.15 - (2007) X-Gauge functionality added.
Version 3.16 - (~2009) AVG and TFC X-Gauges included in firmware.
Version 3.17 - (2009) Minor bugfix release for the Gallons/Litres to Empty X-Gauge, sometimes the word Gallons or Litres would flash across the Gauge screen on some vehicles.
Version 3.17mb - (05/2010) Minor bugfix release for some vehicles that use the KWPF protocol (particularly vehicles that used a Mercedes Benz engine) Fixes a timing issue that prevented the SGII connecting to some KWPF vehicles.
Version 4.02 - (04/2011) Major release. Changes to menu system and setup options. Turbo Boost gauge and Horsepower gauge added as standard gauges. Performance Monitor added - record, save and playback up to 8 performance runs. Revisions to Trouble Code clearing protocols. Fuel consumption can now be displayed in kilometres per litre or Litres per 100 km. Alternate method for clearing DTCs. Horsepower gauge adjustment. Changes to the on screen Menu structure. For more information feel free to download the latest user manual for the new v4.02 ScanGauge2 here.(10.6mb)
Version 4.05 - (07/2011) Addition to the Performance Monitor that allows a performance run to be recorded in metric as well as imperial units.
Version 4.06 - (09/2011) Re-introduction of the Mercedes Benz fix that was added to 3.17mb. The fix was mistakenly left out of 4.02 and 4.05 and is only of benefit to a small number of early model Mercedes Benz vehicles that use the KWPF protocol.