C5 2.0 HDi Low pressure pump

[columbusautos]

Got a c5 2.0 hdi 2002 to play with AA diagnosed as low pressure pump failure i have diagnosed bad pump circuit.
When jumped with 12v the pump runs engine might even start if i hadn't changed the internals of the filter and failed to reassemble properly - diesel all over the floor.

When the ignition is on or the engine cranked the feed for the fuel pump is between 6 -10 v and pump doesn't even kick.
Is this controlled by the bsi?
Got any smart ways of checking.repairing this fault? Any guidance would be greatly appreciated
ta very much

[Peter.N.]

I think the pump is controlled by a relay, the fact that you have some voltage there would seem to indicate that the circuit is functioning but you have a high resistance somewhere, could be the relay or a wiring fault.

Peter

[columbusautos]

from what i read last night the same relay feeds at least 3 other things and nothing else seems to be malfunctioning so i think i may have a short in the pump loom running to the rear of the car. Gonna get the multimeter out and have a play later.
thanks for the reply

[Gibbo2286]

Where are you picking up the earth for your test meter? I found when I tried to test the voltages there that I could only get a reading of 3 to 7 volts but then found that the tank wasn't earthed properly and had to run a cable elsewhere to get a proper reading.

[columbusautos]

Door hinge/lock - power probe back to the battery.
I have traced the fault to the fuse box in the engine compartment by the battery. There is a burnt out pin on the central multiplug which is the feed to the fuel pump.
Sorted my filter problem now just got to get the pump to run off the ignition again.
Here are some photos is this fuse box replaceable with out coding or will it be similar to a bsi?



Sorry for the bluryness but its the best i could do.
Probing with a multimeter i've got 8v's roughly feeding the circuit to the pump which can drop out to nothing. If the fault starts here i will probably have to source another fuse box and repair the plug?
The large feed from the battery to the fuse box is showing battery voltage but the output from this burnt pin is not. From what i can see its a printed circuit board inside so probably beyond my bodging capabilites.

So the big question is could i straight swap this item with out coding if i can find one in a scrap yard?

[columbusautos]

The answer is yes went to a scrap yard and ripped another fusebox out of a 207 hdi and plugged her all up turn the key pumped stirred into life and cranked her over and she fired straight up.
Jobs a good en me thinks

[Xantidote]

That was quick - well done

[BinaryBen]

I have suffered an intermittent pump failure for years, RAC and garages had always got it going but not sure how!!
I have just had a new low pressure pump fitted, the car was good for about 4 weeks, then it failed again. I put a test light on the red thick wire on the connector to the pump, and found I had no 12v at all. I then did something I was not to happy with, I ran a direct wire from battery to this connector, the pump ran and the car started (excellent). Having read this forum, I wondered if i had same problem on connector plugged into the central fuse panel. I removed all 3 plugs from the central fuse box (under bonnet) and didn't see any burnt pins. But the act of removing the connector and re inserting was enough to clean the pins, and now the pump runs fine without my hot wiring. Thank you for posting your findings, it helped me greatly.

[Hell Razor5543]

Sometimes you can get grot build up on the connectors, which would increase the resistances and cause problems. The act of unplugging and plugging in can scrape some of the grot off. It could be worth taking each plug out, going over them with a toothbrush (and if you can get hold of some) using proper contact cleaner on the plugs and sockets to get rid of any residual grot.