C4 Grand Picasso - Fuel Level Incorrect - Recalibrate?

[findmak]

On my C4 Grand Picasso - 2015, I have an issue where the fuel gauge is showing 3 bars but I ran out of fuel. Is there a way I can recalibrate the fuel gauge with diagbox or is it a dealer job?

[GiveMeABreak]

The most common reason for this is adding small amounts of fuel. Citroen's advice is to tell customers not to do this.
The dealer can check the live parameter measurements to check for the gross and displayed amounts of fuel. This requires the tank filling up of course, but after checking this:

1) If the amounts are the same, then the advice is don't add small amounts of fuel.
2) If the amounts are different, they can initialise the fuel gauge - but only in this specific case.

They may well charge you for a diagnostic to do this. So my advice is to fill the tank up a few times and if applicable, don't keep the tank low and add small amounts of fuel.

[Peter.N.]

Try a BSI reset, it worked on my old Mk1 C5.

Peter

[findmak]

Yes I have been guilty to topping up small amounts.
The dealer said they had a information bulletin to do a software upgrade.

Can I check the parameters using the diagbox?

[GiveMeABreak]

You can.

You will need to locate the live parameter tests (likely under the BSI or engine ECU), make sure the tank is full and then run the test to see if the max fuel reading matches the displayed reading.

If the dealer has a TSB relating to the issue they may not charge you - did you clarify this or not? If they are not going to charge, you, then let them sort it for you.

[findmak]

They said they would charge me for 1 hour to do the software update.

[GiveMeABreak]

So I'd expect that will be at least around the £100+ mark.....

[wheeler]

Some PSA models do actually have a reset function on Diagbox to reset the fuel gauge. I cant remember if its in the BSI or instrument panel, I don't remember the exact wording of it either, I think it may be reinitialise fuel gauge. I done it on my neighbor across the roads 307 HDi maybe around a year ago that the fuel gauge was playing up & it was apparently fine till he got rid of the car.
Not sure if its available on all models or not but worth a look & a try before shelling out for a software update.

[findmak]

Some PSA models do actually have a reset function on Diagbox to reset the fuel gauge. I cant remember if its in the BSI or instrument panel, I don't remember the exact wording of it either, I think it may be reinitialise fuel gauge. I done it on my neighbor across the roads 307 HDi maybe around a year ago that the fuel gauge was playing up & it was apparently fine till he got rid of the car.
Not sure if its available on all models or not but worth a look & a try before shelling out for a software update.

Thanks Wheeler, I couldn't see it in the BSI, will check again in the morning.
Do I need to fill the tank fully before doing the reinitialise fuel gauge?

[wheeler]

No, it doesn't require the tank to be filled.

[findmak]

In the BSI in engine measurements, it showed a 1 litre difference between Fuel level measured and fuel level calculated, I found a Force Fuel gauge data in the BSI ECU in Learning menu. After doing this both the Fuel level measured and calculated are the same but it doesn't equate to the 3x bars I am expecting it to reduce by.

[wheeler]

I’d try filling it up now first & see how that goes.

[findmak]

Just been to the dealer who had the TSB, hey re-calibrated the gauge the same way I did, but said there was a difference, but the gauge is still showing the same as before. Do you think it is sorted but I just need to follow Wheeler's advice and fill up to the max and see how it goes?

[GiveMeABreak]

Just fill it up and see if after driving a while with a few trips of starting the car whether the gauge starts going back to full. If not take it back to the dealer.

[findmak]

Thanks Marc, will do.