Disco 4 (LR4) Fuel guage issue

Good afternoon folks,

My 2009
D4 has just been to garage for MOT and a new passenger side blend heater motor.

Motor all sorted however randomly now the car is saying that it has Zero fuel in and zero miles on the range?

We’ve dropped more fuel in her and no difference, still reading zero, fuel light on and no codes /faults showing when plugged in?

Any help or advice greatly appreciated.

Hi probably the fuel gauge sender or it's wiring is fubar, https://www.disco3.co.uk/forum/discovery-4-fuel-tank-removal-wiring-sender-finished-178913.html

A known issue is the sender unit in the tank if the battery was disconnected while work was going on and the fuel was low it can cause the car to go into safe mode stopping it from starting if the fuel gauge reads empty.

Hopefully yours is still running if it goes into safe mode you need diag to get it reset before it will start again.

biketeacherdave said:

A known issue is the sender unit in the tank if the battery was disconnected while work was going on and the fuel was low it can cause the car to go into safe mode stopping it from starting if the fuel gauge reads empty.

Hopefully yours is still running if it goes into safe mode you need diag to get it reset before it will start again.

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The 'known issue' is L322 specific, given that the engine is still running means that the ECM is seeing some fuel in the tank, otherwise the 'driver inducement' misfire would be occurring, followed by an engine shutdown to protect the HPFP from running dry. Personally I'd try a battery disconnect / reconnect before anything else - make sure the vehicle has fully shut down (keys out, doors closed, bonnet open for 20 mins) before disconnecting the battery, then leave disconnected for 15 mins before reconnecting. The lack of DTC's suggest the wiring is intact and both sensors are providing some sort of output, if the battery disconnect / reconnect doesn't sort it, it's time to get the multimeter out...

The three wires for the level sensors are connected to the CJB and values broadcast on HS-CAN.