Digital Fuel level indicator faulty

This is the Forum for all your Citroen Technical Questions, Problems or Advice.

Moderator: RichardW

Post Reply
Frodoisdead
Posts: 11
Joined: 07 Nov 2018, 00:00
Location: Torquay
My Cars: Citroen C5 Eatate 2006 2.0 diesel

Digital Fuel level indicator faulty

Post by Frodoisdead »

Hi, got C5 2.0 diesel mk2 (2006) and digital fuel level indicator is playing. Not analogue but the one on the digital screen. It shows jumping mpg from 15 to 999mpg and keep changing. Also how many miles left of fuel in the tank, always jumping from one number to another. I remember had same problem when i had Picasso c4 (2008). How can this be fixed, is it some sort of sensor that needs replacing? Mamy thanks
MikeT
Posts: 4809
Joined: 11 Jun 2007, 16:17
Location: Christchurch, Dorset. UK
My Cars: 2005 C5restyle 1.6HDI 16v 110hp VTR Estate
2008 C5 X7 1.6HDI VTR+ Saloon
x 231

Re: Digital Fuel level indicator faulty

Post by MikeT »

It's not faulty, it's how the Trip Meter works. Check your handbook or experiment by pushing the end stalk button on the right. It cycles between three displays. The first is live readout, the other two are accumulators.
Frodoisdead
Posts: 11
Joined: 07 Nov 2018, 00:00
Location: Torquay
My Cars: Citroen C5 Eatate 2006 2.0 diesel

Re: Digital Fuel level indicator faulty

Post by Frodoisdead »

It was working fine on picasso until one day and started flicking like that with mpg changing every second! I don’t believe it should work like that
MikeT
Posts: 4809
Joined: 11 Jun 2007, 16:17
Location: Christchurch, Dorset. UK
My Cars: 2005 C5restyle 1.6HDI 16v 110hp VTR Estate
2008 C5 X7 1.6HDI VTR+ Saloon
x 231

Re: Digital Fuel level indicator faulty

Post by MikeT »

Are you saying it doesn't follow your right foot, which is how it should work?
Online
User avatar
Paul-R
Donor 2023
Posts: 6916
Joined: 07 May 2009, 16:24
Location: Wirral, NW England; Vaucluse 84, France
Lexia Available: Yes
My Cars: 2015 1.6 Blue HDi 120 Peugeot 308 Active SW
2013 2.0 HDi 163 C5 Exclusive Tourer
2003 2.0 HDi 110 C5 Exclusive Estate (Gone)
2001 2.0 HDi 90 Xsara Estate (Gone)
x 1369

Re: Digital Fuel level indicator faulty

Post by Paul-R »

First of all it's not a digital indicator of fuel level, it's an indicator of fuel consumption. As others have said it shows one of three mpg states. Two of them are based on an average over the distance as recorded by the two trip measurements and the third is a slightly smoothed instantaneous mpg readout.
Frodoisdead wrote: 04 Dec 2018, 01:39It shows jumping mpg from 15 to 999mpg and keep changing.
That is exactly as it should be. It allows you to see the effect of backing off your right foot (!) and how hanging on to a high gear can sometimes be worse than allowing more revs in a lower gear.
Frodoisdead wrote: 04 Dec 2018, 01:39Also how many miles left of fuel in the tank, always jumping from one number to another.
Now that shouldn't be changing rapidly at all except, possibly, just after you've filled up with fuel. I would expect it to change slowly as it counts down the amount of fuel left in the tank. If it is rapidly changing then that's not right. In fact I've not heard of that happening before.
As I get older I think a lot about the hereafter - I go into a room and then wonder what I'm here after.

Inside every old person is a young person wondering what the hell happened.

"Trying is the first step towards failure" ~ Homer J Simpson​
Gibbo2286
(Donor 2020)
Posts: 7171
Joined: 08 Jun 2011, 18:04
Location: GL15***
My Cars: 2006 C5 2.0 Litre HDI VTR Automatic Estate.(now sold on)
Currently Renault Zoe 2014 ZE
x 2500

Re: Digital Fuel level indicator faulty

Post by Gibbo2286 »

Mine does the same, it is giving the actual instant fuel use depending on road and load conditions, downhill with engine braking it will show up to 999mpg because it's not using any fuel, up hill under load it can be down to 15mpg.

The distance to the need to top up works similarly, if you're cruising steadily it might estimate that you can go 60 miles, if you drive hard that estimate will come down accordingly.

The actual average mpg shown over the whole period on mine is around 39mpg, most of my travel is local pottering about with only a long distance trip monthly.
Man is, by nature, a lazy beast, he does not need twice encouraging to do nothing.
Post Reply