THE C4 has not been behaving itself over its first few weeks in our care. The first hint of teething trouble was during a trip down to the south coast.

After several months with Ford’s excellent touchscreen satellite navigation unit, regressing to a button and dial-based input system was always going to be a backward step.

Destinations can be inputted using a dial and text message-like buttons on the dashboard or the steering hub. It is very fiddly and the hub-based dials operate the wrong way round. Want the cursor to go up? Roll the dial down, and vice-versa.

Once the correct screen has been wrestled to the display, the system is unable to accept postcodes for destinations. You can find addresses by latitude and longitude, but who on earth would?

Zoom in or out of the screen and the processor often hangs, leaving a half-finished map on the screen and taking up to 10 seconds or so to catch up. With the preferred zoom level set, progress was good. The maps are clear and guidance notes appear in good time.

But then the first major strop arrived. Approaching the A1/M25 junction at Potter’s Bar, the NaviDrive, as it is called, decided to stop.

The arrow representing me ground to a halt on the map. Seconds later, everything else froze as well. The CD changer stopped mid-lyric, and no amount of button pressing provoked any response.

I pulled off the road and restarted the car. The computer spluttered into life and then froze again. Another restart finally got things going.

About two weeks later, driving in the opposite direction on the same route, the same thing happened again. In the same place.Oddly, since that incident the NaviDrive has worked out that Potter’s Bar is best avoided and now takes me through St Albans.

Citroen says our problems are an isolated issue and may well be due to an external factor interfering with the technology on our car. Spooky.

Model: Citroen C4 Coupe 2.0 HDi 16v VTS
Price (OTR): £18,095 (£20,220 as tested)
Mileage: 6,102
CO2 emissions (g/km): 142
Company car tax bill (2005/6) 22% tax-payer: £49 a month
Insurance group: 10E
Combined mpg: 52.3
Test mpg: 37.3
CAP Monitor residual value: £4,975/28%
HSBC contract hire rate: £368
Expenditure to date: Nil

Figures based on three years/60,000 miles