range gauge

[marks carlsson]

hi all
can somebody please tell me what controls the range gauge on the trip computer on my carlsson
everything else works but the range gauge has madeits way down to zero and now won't budge

help
thanks
mark

[wrighar]

Range (DTE) is I think derived from a number of factors.

1. estimated volume of fuel available in the tank (handy that one...).
2. the current average fuel usage since last reset.
2. the fuel usage over the last 20 minutes.

The DTE, average fuel consumption, SCC bits like speed warning, dist to dest, average speed etc all rely on the retriggered speed square wave from the speedo head unit, which in turn gets is signal from the speed transducer on the gearbox.

Andrew

[marks carlsson]

[img]/saabforum/images/graemlins/confused.gif[/img]

[djtaylor]

I think the translation is that if the speedo is working then the square wave speed signal that is fed from the speedo to the SCC is not getting through because the SCC isn't sensing movement but is still seeing fuel consumed.

Broken cable? Poor contact?