:confused1:

 

In the repair manual, section EF & EC , Page 151, Diagnostic procedure 39 under “A – Check power supply” it says when checking voltage between fuel pump connector terminal "A" and ground Battery Voltage indication should appear for 1 second after turning ignition switch "ON"

 

Has anyone had it that the Battery voltage indication appears and then stays there? Instead of going off the voltage stays there permanently and goes up to almost 14 Volt when the engine is running.

 

As always, any ideas are greatly appreciated.

 

Cheers

 

Maz

whats the nature of the problem?

The Fuel Pump Control Module keeps blowing; I´m on my 3rd Module and aleady I can smell that smell of electrical burning coming from th FPCM.

 

I´ve checked and replaced the Fuel pump relay.

 

I have a brand new OEM Fuel pump

 

I´m guessing the fact that the power to prime the pump stays on constantly, plus the normal power that is switched to the pump when in operation is causing the problem.

 

I just can´t explain why the power remains on the connector when it should go off after 1 second :confused1:

Sounds more like your burning it out due to too much power getting too it. not because its on to long. check under the hood, at the fuel pump fuse (smaller of the fuse boxes) make sure its a 30Amp fuse in there.

 

trace it back from the fuel pump, but i would imagine with it being so late in the chain. it will before the FPCM your getting the excess power. do you have a link to the wiring diagram?

I´ve checked the fuse mate, and all the relays in question, The problem is I can´t figure out where the cable leads to. Two of the wires on the connecter in question are for fuel level and fuel warning light. the 3rd one is the one where the power should turn off after 1 second, but the power stays there, even if you remove the fuel pump relay and FPCU.

 

I´m guessing the 1 sec "burst" of power is to prime the pump,,,,but where is that cable comming from..is there another relay inbetween that could be stuck in the "on" position permantly ?

 

I´m kind of grabbing at straws here mate

OKay...sorry guys, forget this thread, I´ve been refering to the Euro spec manual 2+2 while working on a US-spec 2 seater :hammer:the wiring is completely different.

 

:oops:

OKay...sorry guys, forget this thread, I´ve been refering to the Euro spec manual 2+2 while working on a US-spec 2 seater :hammer:the wiring is completely different.

 

:oops:

 

lol let us know how you get on.

Update

 

I´ve checked all wires from ECU to relay, from relay to FPCM and from the

Control module to the pump for continuity – All OK

 

The Fuel pump is OK with 0.5 ohm across the connectors

 

The relay clicks and sends the 12 volt to the pump for 1 second. To prime it

 

The FPCM seems to be working OK too in that it passes the 12v constant from the relay

To the pump once the car has started and the white wire passes on the variable ground path.Measuring the voltage coming from the FPCM to the pump it does exactly what it´s supposed to do: Primes pump, 12-14v for the first 30 seconds of starting, then drops to 5.9 – 6 volts on idle.Volts increase as you accelerate too.

 

So why does the Fuel pump control module get so hot after a 10 minute drive , starts to give off that electrical burning smell- that´s when I switch the car off,

 

Faulty FPCM ? two in the space of a few months ?

Check the earths, you might have a bad earth so it could be pulling the current from the wrong place

 

Paul.

Problem solved!

 

Unbelieveable!...after checking everything, and then checking it all again I took a closer look at the underside of plate where the fuel pump is connected beneath. A very close inspection of the contacts there revealed a single strand of electrical wire was bridging the plus and minus pole. Almost impossible to see. we didn´t even see it when we resoldered the fuel pump wires on there.

 

removed the wire and now eveything works fine without the FPCM getting too hot. Tomorrow I have to drive a longer distance so I´ll know for sure after that, but fingers crossed.

 

Cheers.

 

Maz

 

:)

okay long distance drive on the Autobahn and everything is working fine.

 

end of the electrical / fuel supply problem.

 

Thanks to everyone for their input over the months and a special thanks to JeffTT.

 

Maz

 

:)

okay long distance drive on the Autobahn and everything is working fine.

 

end of the electrical / fuel supply problem.

 

Thanks to everyone for their input over the months and a special thanks to JeffTT.

 

Maz

 

:)

 

Nice one Maz, got to say your one determined guy, well done!

 

Jeff TT