No power getting to high pressure fuel pump

[Odd-job]

Hi I have a 2006 2.0 hdi Citroen C8 that has no power getting to the high pressure fuel pump so the car will not start
I have checked fuses which are all ok so was wondering if it could be the fuse box itself any help would be much appreciated
Thanks

[CitroJim]

Welcome to the forum

If all fuses are good then the immobiliser remaining active can potentially be the cause of this... Is it being deactivated when the key is in place and the ignition is on?

A diagnostic session would be a good next step to see if any faults are present that might account for it...

[wheeler]

Can you confirm that you mean the high pressure pump on the engine & not the pump in the fuel tank?
Which connector & pin number are you checking for power at?
On this car the immobiliser being active should not stop any power to either of the fuel pumps. You should also get a warning message on the central display about it.
Maybe a little more history of the fault? did it cut out whilst driving or just not start one day? was it in regular use prior to not starting?
Would really need the VIN or reg to check up a wiring diagram.

[Odd-job]

hi sorry at work at the minute so not able to get the reg
not had it long and the wife was driving it and it went into limp mode and when she stopped it cut out and would not restart so called the AA and ask if he could take take it home as i like to see if i can do the work and save a bit of money but he was adamant that i would not be able to fix it so took it to our garage
the aa said after putting it on his machine it had a few faults but the main one was something about the high pressure fuel pump
the garage then had it and he thought it could be the fuse box as no power was getting to the high pressure fuel pump so tried getting a secondhand one but had no joy so he suggested taken it to a main dealer as if it was the fuse box the they would be the only ones who could programme the fuse box

[wheeler]

The AA would have sent you an email after attendance that would have a note of any fault codes attached to it. Do you have a note of this?
The under bonnet fusebox does not need programmed on this car.
Is the low pressure pump operating?

[Odd-job]

here is the report

We have arranged for recovery of your vehicle.Patrol found the following fault code/s:System : Engine control 1 - 75M / Diesel EDC 15C2-1xP1442 - Fuel additive system. Error Message : Additive quantity in DPF exceeded.P0101 - Air flow or air mass meter (bank 2). Error Message : Signal improbable.0403_10 - Unknown fault. Error Message : .P1451 - Charge-air preheater. Error Message : Open circuit.1460_10 - Unknown fault. Error Message : .0243_10 - Unknown fault. Error Message : .1112_22 - Unknown fault. Error Message : .P1607 - Driving speed limitation. Error Message : Open circuit.Cut out won't start, visual inspection of engine all ok. Check live data, appears to be not building fuel pressure. Possibly high pressure pump. CRT to garage. Requires full diagnosis and repair. Member getting lift home. Engine Oil Level Ok. -

[Odd-job]

Vehicle Registration Number

RJ06YFA

[wheeler]

P1112 = high pressure fuel monitoring fault, This could actually be a red herring. The high pressure side of the fuel system is monitored but the low pressure side is not.
Might sound obvious but first off is there plenty of fuel in the tank? Dont trust the fuel gauge, the can & do lie. No fuel = no fuel pressure.

Did the AA try a sniff of easy start to see if it would fire on that?

Before going any further with this you need to confirm that the low pressure pump in the tank is operating correctly, no low fuel pressure also = no high pressure.
Low pressure pumps are a relatively common failure, If you stick your ear next to the fuel tank you should be able to hear it humming when the ignition is switched on.

[Odd-job]

Hi
Yes wife said she put £50 fuel in on the day before and yes the AA did try easy start and it did start for a few seconds

[Odd-job]

No no humming coming from fuel tank
So how easy is it to get to that pump
Is it from under the car or do I need to remove seats and carpet
Also the car is in economy mode so would that stop the tank pump from operating

[Hell Razor5543]

Economy mode is designed to disconnect (when it kicks in) that equipment that could drain the battery (such as the radio) which is NOT required to start the engine, so the tank pump would not be turned off.

[wheeler]

I’m sure the LP pump on the C8 has no inside access, tank needs lowered. However there is a connector to the pump that is accessible from underneath without dropping the tank. Fist thing i would try though would be to thump the underside of the tank at the lowest point with the palm of my hand whilst some one tries to start the engine, sometimes (temporarily) kicks the pump back into life.

[Odd-job]

Hi
Sorry been really busy but had a chance to get under the car today so checked the connector and thumped the tank but car still won’t start

[Gibbo2286]

Can I just say that the 06 HDI may not have an in tank LP pump, if it's that same as the C5 2.0 litre HDI the low pressure and high pressure are both served by the pump under the bonnet.