Skem55

can anyone help, yes ive search before ppl ask!

impreza wouldnt start this morning, so have a quick nosey abt and it appears the fuel pump aint priming, from reading on here and other forums. im now trying to figure out how to put a constant 12v to the pump to see if the pump has failed or if i go back to immobiliser n by pass that?

can any one tell me which pins is the positive and negative so as to check pump is failed or working

cheers stu

or if any autoelectrians near farnborough hants who could spare me an hour??

mcvicar

Before you try anything else, use a rubber hammer and give the top of the pump a little tap, had several that get stuck, including a non runner I've just bought recently, that had been laying for over a year, done the trick and still running. Obviously if this does work, a new pump would be the next step.

Skem55

Will give it a whack lol just weird how's it's been fine then this morning just nothing!!

Finbin

Hi, this happened to me a couple of years ago, read the following thread for some good advice and what I found out to be the problem.

https://www.scoobynet.com/general-tec...-car-died.html

Skem55

Link don't load!?😔

Finbin

Link worked at home this morning, but not now?

Car died a couple of year ago after about half a mile drive home.

This is what I found, green plug relay is the fuel pump relay (which is situated behind dashboard need to look up from the pedals) this relay has four wires going to it:-

Green/red (coil terminal) from fuse box inside car (fuse 11) this becomes live when ignition is switched on (+12volts).
Green/black (coil terminal) from ECU this provides the earth for coil, which looks like this controls the operation of the relay, switches off relay when up to pressure.
Black/red (thicker) contact terminal from main fuse box (slow burn fuse 5 in the engine bay)
Black/yellow (thicker) contact terminal to fuel pump

The black/yellow wire after about a couple of inches has a soldered joint under some heat shrink and the wire changes into a plain black wire which disappears into a loom!

Unsure where this went, I then started to follow the wires back from the fuel pump. As people know you get to this by removing boot carpet and access plate in the boot. The plug has five wires, I was only interested in the thicker ones which were:-Black/red and Black. I then removed the rear seat base to discover a plug/socket joint where the black/red wire changes into a black/yellow wire. Following this into a loom which runs along the inside of the sill to the front of the driver’s door. I remove the trim to prove I was following the correct loom.

At the end if the loom, wires go into a white plug/socket joint there I found the black/yellow wire. The black/yellow wire after about a couple of inches has a soldered joint under some heat shrink and the wire changes into a plain black wire which disappears into a loom! I can only guess this goes to the alarm/immobiliser?

So I did what anybody else would do after chasing this for a long time and having most of the car stripped, I run a new piece of wire between the two soldered joints.

Hurray, car now starts and runs.

Then all that was left to do was put car back together.

If you has any questions or does not understand my writing drop me a message.

Cheers

Skem55

I think I understand all of that lol it helps that you've explained where each wire relates too give me and clearer idea now of where to trace too cheers dude

thunder8

iTrader: (1)

Silly question under the drivers passenger rear seat is a 3 pin plug for pump these are known for melting ....my car did the same last year i got a live to pump and it worked to get me to akarm spiecalist who took my old alarm out (sigma) had melted so new cat 1 alarm fitted :-)

Skem55

Ok so I've 12v at the relay and 0v at the pump this is sounding like as you mentioned thunder8 the three plug under seat has melted is this easily seen or am I being blind??

Gambit

iTrader: (6)

Itll be the immobiliser relay for fuel pump which is that 'soldered' wire that is talked about in the post above, you can remove it & bridge it, then the immobiliser will just work on the starter.

The immobiliser relay cannot be fixed as its inside the immobiliser control unit which is bolted up behind steering column

Skem55

Makes sense now, so can I just leave the original cable T onto it and run a cable to the black/red on the pump?

Gambit

iTrader: (6)

Yeah the immobiliser wiring is just spliced into it, so just unsplice and reconnect the 2 main thick wire fuel pump wiring and then bridge the immobiliser wiring.

Skem55

Gambit, 2 main cables now I'm getting lost lol

Skem55

Well boys (and girls, political correctness and all that *****) thanks for all ur help she lives! Now all I gotta do is hide this sodding cable down the car lol

Gambit

iTrader: (6)

Did you just remove the immobiliser wiring from fuel pump wiring?

What I was talking about is you can see the difference in thickness of the main fuel pump wiring compared to the thin immobiliser wiring they splice in.

Skem55

Just snap locked at each end before soldered joints haven't removed the immobiliser cable as was unsure if it would affect anything else?? Any one know if I can remove it??

Gambit

iTrader: (6)

just leave it bridged

t1gger

iTrader: (2)

Just had same problem car stopped 3 times last week then stopped for good on Wednesday, got a car alarm man out who had previously done me a new remote fob .turned out to be the sigma alarm. .it was not letting enough voltage through to pump .so he cut it out from alarm.

Skem55

Yea basically wat I've done only left the original cabling in situ and bridged before the soldered joints at either end, cheers to all above for the help!

Gambit

iTrader: (6)

The next immobiliser relay to fail will be the indicator flasher relay, youll know this as the driver indicator sticks on. You can usually reset by arm/disarming alarm but can look stupid as you sit for a minute arm/disarming!!

t1gger

iTrader: (2)

Funny thing ive got a fozzy and some times drivers side indicator flashes some times on start up.but been like that since ive had car

mickywrx

iTrader: (29)

Had similar on my car last year, kept randomly cutting out and not starting, mine wasn't an OEM alarm though. I'd tried swapping the relays etc.

Auto sparky cut the immobiliser wire out and it was fine, cost me a new alarm though.