e36 no power to fuel pump relay. HELP!!!

[KingKalie]

Okay so here it is, I'm having some technical difficulties with some electrical gremlins..
:dunnoanymore:
as the title says i'm not getting any power to the fuel pump relay or fuse 18, the dme relay works the car has spark the fuel pump works when run directly off of the battery, but no power to the pump, fuse 18 or relay. Any suggestions?? can this be due to a faulty cam or crank sensor? and another thing i noticed was when the fuel pump was jumped and the fuel was going through the rail the injectors would not pulse/fire, all help and advice is appreciated :thumbs:

 

[Waseem 333i]

Might be the ews or alarm thats faulty

 

[KingKalie]

Might be the ews or alarm thats faulty

I'm not sure it could be that as the car has an aftermarket alarm installed, but if perhaps it is the ews do you know how to bypass it?

 

[Waseem 333i]

I forgot how to do it. I am sure someone with more knowledge will help you. Should be via pm. Its not a good idea leaving these tricks for thieves to see granted they already know about it

 

[KingKalie]

I've narrowed it down to the blue and green wire from terminal 87 that is not getting power/signal to it, is there anyone that can shed some light on this?

 

[JayDrft]

May help, or it may not - have you checked for continuity between pump and fuse box?

I recently fault finded with a buddy on my e34 - took many a trips back and forth, but we found a break in the wire feeding from the fuse box to pump. So check power between relay to fuse box and fuse box to pump...

I hope it helps.

 

[KingKalie]

Thanks for the reply, I tested the wires at the pump a while back and could not get a reading there, i will however go through wires to check for a break in the wire as susggested :thumbs: I also don't see any power at the fuse when the relay is jumped did you come across this too when the plug wires were broken?

 

[KingKalie]

Okay so this is what i've discovered so far..
i tried tracing from the fuel pump back and vice versa
-fuel pump works
-no power at pump plug and no continuity
-no power at fuse 18
-no power at fuel pump terminals until key position 2 (is this odd? as i recall terminal 30 and 85/6 are always hot)
-no reading between terminal 30 and 87 of fuel pump relay when key is on
-when FP relay is jumped i still get nothing
-DME relay and terminals all check out good

can anyone share some wisdom here as I am at witts end and do not want to start tearing into everything when there could be a simple solution, is there anyone on the forum that knows the electronics well that I might be able to take my car to?

 

[KingKalie]

Also it's a 92 e36 (red label 413 if I'm not mistaken), did these even have ews??

 

[KingKalie]

bump

 

[KingKalie]

Anybody???

 

[JayDrft]

Take a long wire through from your fuse box to pump terminals/plug...check for continuity at this point - terminal point to long wire thats connected to the fuse box point

if you just test the terminals, there wont be power or contunity....you need to test from the fuse box to terminal...continuity is to determine a break in the line...

Have you identified which wires are which, cause your fuel gauge/sender gets power from ignition, hence showing power when you switch ignition on. The terminal that you getting power from is probably not your fuel pump power supply but rather your fuel gauge power supply. Move on and check continuity between the fuse box and your remaining terminal points...if you dont get continuity between those points, then you most likely have a broken wire in the harness.

If you have continuity, then check fro continuity between your relay point, to the fuse box...Identify common wire colours between the fuse box and relay box...unless they are in the same box...then remove nuts/bolts and check underneath the box and test from there.

Trust me, I learnt the hard way:cartel:

 

[Prev]

Also it's a 92 e36 (red label 413 if I'm not mistaken), did these even have ews??

The red label DME does not have EWS


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