Fuel Gauge Problems

We have a Freelander 2 TD4. We have just experienced (with a full tank of fuel) the gauge starts at full and then drops to empty and up to quarter full etc. When the needle reaches empty to Sat Nav kicks in and wants to direct you to the nearest fuel station etc. Is this a common fault and would normally assume a faulty sender unit. Or is this a deeper problem involving the sotware etc?

Hope someone can help.

Thanks

Graeme

these freelander do suffer from fuel gauges reading badly but you could have a faulty sender unit

If it hits full on start-up. Its a possible IPK software issue.

If its erratic fuel guage in general, i would look at fuel sender electrical pins to short. It really depends on model year