I have a 69  plate transit custom, it has a digital fuel gauge and the generic pointer needle.

Out of the blue both start dropping like a stone sometimes showing 0-99 miles of fuel left or any number in between,  if it shows 00 for any length of time then the computer would think that it was out of fuel and stop,I would re-start it ran for a while then stop. ...then out of the blue the needle and gauge would go back to normal, but then start to creep back to empty.    Diagnostic computer said it was fuel send to unit. This was replaced but problem still continued,  wiring for the unit was checked and that was all okay. The cluster unit was taken out sent away to be diagnosed but that was found to be okay. So at this point myself and the auto electrician are at a loss.

6 hours ago, Martin861 said:

So at this point myself and the auto electrician are at a loss.

Find yourself a different Auto Electrician. Throwing parts at is not the way to diagnose a fault.

Going to the tank sender connection and removing the plug apply 12v positive signal to the wire that leads to the fuel gauge. The pointer should move to show full. If it does then you have ruled out the wiring and the gauge.

Wow, identical fault currently! Ford have changed the fuel pump, the sender and checked wiring, but still has fault. They want to change the instrument cluster to which I have said no. Now looking for an independent Ford Transit guy who might have a better idea than just speculatively changing parts. 

1 hour ago, Mark Nolan said:

Wow, identical fault currently!

Read my reply above. Disconnect the plug from the tank sender unit. Apply a 12V supply to the plug that leads to the fuel gauge. If the pointer shows full, then you can rule out the wiring and the instrument cluster.

martin861, did you find out the problem with this? my 2019 transit custom has started doing the exact same fault?

28 minutes ago, Iandav710 said:

martin861, did you ....

expect a long wait.

Hello I have the exact same issue did you find the fault ? 

8 minutes ago, Daniwl said:

Hello I have the exact same issue did you find the fault ? 

There's already a suggestion on this thread on how to diagnose the fault, once you've done it, come back to us...

 

The wiring has been checked and they found no faults. Fuel sender unit replaced and speedo head has been tested. 

I am now out of options ?

If you tell me the results of the test procedure detailed above then I can tell you the next step in clearing the fault.

Up to now I have a 100% strike rate of OPW's in this thread 🙁

I will ask them to carry out the above tests, however they said they aren’t willing to take it any further and I require a full system update to be carried out by a Ford garage ? 
 

If the above test shows full what next ? 
If it doesn’t show full what next ? 
I would love to know what the possibilities are as it’s really stressing me out 🙃😢

 

I really appreciate you replying to my post. 

 

thank you 

17 minutes ago, Daniwl said:

If the above test shows full what next ? 

Then the fault is either the tank sender unit or the supply to the tank sender unit.

18 minutes ago, Daniwl said:

If it doesn’t show full what next ? 

Then the fault is either the wiring to the instrument cluster (may go via other modules) or the instrument cluster.

Fault finding needs to br broken down in to logical steps. At each stage the result needs to be analysed to be able to plan the next test.

The tank sender unit has been replaced 

all wiring has been checked via a Ford wiring diagram 

cluster unit has been sent to a diagnostic company and has passed all tests 

Then it must all be working correctly 👍

Or

It's not working, which means some part of this has not been done correctly.  🤔

 

Doesn't the PCM interpret the fuel level readings?

4 hours ago, DaveT70 said:

Doesn't the PCM interpret the fuel level readings

It could very well do, or even the BCM might contribute data. As far as I know the fuel sender unit in the tank is little more than a variable resistor that is used to send a variable voltage to ........ IPC, PCM, BCM ?

This should not be a difficult fault to trace, although it might take a little to to access various wiring points. 

Edit: Based on information that I've just found, this is likely to be a BCM software issue. Rebooting the BCM using FORScan may solve the issue. Failing that then the BCM most probably requires the software updating (Ford dealer job).

Edited March 7, 20251 yr by unofix
New information on BCM

I don't have the schematics for the 2019 Transit, but I do have them for the 2020 Transit Tourneo Custom which I expect will be very similar, if not the same.

Firstly it seems the Fuel level signal is from the Body Control Module (BCM) and the tank sender unit alters the voltage level.

Looking at the schematic the BCM provides a fixed ground (0V) to one end of the variable resistor and also to the slider of the resistor. The other end of the variable is connected directly to the BCM. As the level in the fuel tank changes, then the signal to the BCM is connected either more towards 0V or the resistance to ground is increased. This should be simple to replicate using an external variable resistor and connecting it to battery ground and the other side to the BCM signal input.

Maybe water ingress into the bcm/ connectors causing corrosion? 

2 hours ago, iantt said:

Maybe water ingress into the bcm/ connectors causing corrosion? 

Ah but it has been looked at by a professional at the Ford garage, they would have checked that 🤣

2 hours ago, unofix said:

Ah but it has been looked at by a professional at the Ford garage, they would have checked that 🤣

Yeah right!! 

This is what the garage have sent me as I requested a description of works that have been carried out. 
 

Fuel tank removed and fuel pump module with level sensor replaced  after subsequent failure the tank was dropped to access wiring  again . Wiring was tested from the FPM to the N/S/F chassis leg where a cluster of multi plugs are located and are prone to water penetration and corrosion however all were clean and moisture free . It then became a bit more complicated as we had no wiring diagram at this time so located the BCM under O/S of dash removed it and inspected connectors and terminals again no corrosion or moisture but also unable to trace the correct wires . Located a wiring diagram and found the fuel gauge wiring on a  2.0 litre Transit  isn't wired through the BCM  only the 2.2 litre is wired through the BCM . Yours being a 2.0l has only 2 wires , earth wire leaves the instrument multi plug at pin 7 goes through 2 multi plugs to the tank and FPM at terminal 3 which has 0.07 ohms resistance . The return wire back to the instrument panel leaves at pin 2 passes through again 2 multi plugs then up to the instrument panel plug at pin 1  . Resistance test between pin 1 and 7 at the instrument connector reads 52 ohms which is the resistance reading from the level sensor this will increase / decrease with fuel tank quantity . The 2 multi plugs mentioned above were also disconnected and wiring traced tested and readings confirmed correct to my knowledge . At this point the instrument cluster was sent for inspection and found to be okay . Admitting running out of ideas we contacted  an acquaintance at a ford dealer in Forfar for some advice we were told as all avenues seemed to be exhausted it may require a software update to repair.

A very informative fault report !!! 👍

Is this problem with the fuel gauge always present or is it intermittent ?

Also very useful to know that this is the 2.0 Transit (perhaps worth updating your profile to show it's a 2.0 EcoBlue).

the fault is intermittent, I drive it for 4 days and no problems then it was out of use for 2 days turned it on and no fuel. I drove it for one hour no problems then it started to slowly go down to 0. 

Did you get a fix for this issue? I have the same problem. 

Cluster unit