SLROC Forum

Well Gents / Ladies, i've spent the last 2 hours searching and ive now got 2 answers with which to go by, im now asking is there a possible 3rd.

A week ago i jumped in my TD5 90 Defender, key in the ignition and i noticed the fuel pump isn't running, took the key out put it back and bang it jumped to life and done so until this morning when everything is working apart from my fuel pump, ive checked all fuses OK. I have got some water in the drivers seat box from driving in heavy rains.

1) Dead Fuel pump
2) Yellow relay under drivers seat or
3)

And is there a way to check before i drop the tank and the relay.

Thanks in advance   

Relay can be tested with 12v across coil side to activate electro magnet which should produce audible click when energised and multimeter set to ohms measuring the switch which should dependant on coil state should switch from open circuit to closed circuit,  or you could have a look in fusebox and find a simular relay like the light yellow relay and swap and see if the lights come on.


The previous owner to my 90 had replaced the fuel pump as he left a hatch he made in the rear floor similar to what I have seen fitted as standard on Discoverys .

Hope this helps

Ok, ive now discovered the pump is good, ive traced continuity from the engine bay right back to the fuel pump all is good there, now when i get to the relay behind the gear shifter there is a green relay that looks as if the socket has had some heat and if i bridge the pins 30 and 87 the fuel pump comes to life..

How do i test the relay as i dont have a spare one of these!

You need to apply a 12V supply to terminals 85 & 86.
You should here the relay 'clicking' when it energises.
You say the socket looks as though it has had some heat. Have a close look and check all the connectors in the socket are fully home. If it's getting a bit hot that suggests a poor electrical connection somewhere.
Are any of the connectors on the relay looking a bit dark coloured? If they are that is probably the faulty one. That might give you a clue.
If the relay is energising OK and all the connections appear sound then the relay contacts are stuffed. Bin it and get a new one. 

Thanks for the Replies, Im completely lost now.

1)  All wiring front to back is good for continuity
2) Fuel pump is good, tested from green relay by gear shifter.
3) Checked relays with 12v supply and multimeter and they are all good
4) all fuses are good

And yet i still have no fuel pump when i turn the ignition on....could it be my ECU or even ignition?

Is there a immobiliser fitted ?
http://www.legionlandrover.com/manuales/electrical%20schemes%20-%20defender%20td5%20(1999).pdf
Website has electrical wiring diagrams

Water + ECU usually means foosty (technical term!) connections, try disconnecting / reconnecting ECU plugs to see if it makes difference, ECU may have to be opened up to be dryed out properly if you flooded the seatbox with water.
  Ps,  it would be nice if the oil coming into the ECU from the injector wiring loom could serve the purpose of keeping the water out !!!!!!!!
  More Ps,  fuses in seatbox, particularly 20A no 4 for pump relay, remove and check for foostyness.

Is there a immobiliser fitted ?
http://www.legionlandrover.com/manuales/electrical%20schemes%20-%20defender%20td5%20(1999).pdf
Website has electrical wiring diagrams

Hi Vag, simple TD5 mine, there is no immobiliser..

Water + ECU usually means foosty (technical term!) connections, try disconnecting / reconnecting ECU plugs to see if it makes difference, ECU may have to be opened up to be dryed out properly if you flooded the seatbox with water.
  Ps,  it would be nice if the oil coming into the ECU from the injector wiring loom could serve the purpose of keeping the water out !!!!!!!!
  More Ps,  fuses in seatbox, particularly 20A no 4 for pump relay, remove and check for foostyness.

Hi there ive had all the fuses out and all are shiny with no Foostyness, Lol the oil in the loom issue was dealt with a few months back as it was quite bad and after rectification the plugs where loaded with silicon grease ( dielectric ) so everything in there is safe i hope. what is baffling is the way it stopped, a week earlier it did the same thing and after attempting it a couple times i took the key out put it back in and it worked, then she was fine until friday when the same happened and has never come back..

trying to get my hand on a Diagnostic machine is proving harder then i thought, so i think a purchase will have to be made, can anyone tell me a good inexpensive unit to buy..