not really sure but hope this helps.
http://bmwe34.net/e34main/maintenanc...MW%20525iT.pdf
'94 530i: Getting ready to install a new fuel pump and fuel sending unit...as soon as it stops raining & snowing outside
Question: The fuel sending unit has two wires that attach to the pump. One is purple and one is brown. How do you tell which is the positive and which is the negative?
Those wires have the older "ring terminal" connectors for the older style pumps. The new pumps require you to cut those wires and attach plug sleeves which then slide onto posts on the pump. The pump indicates which post is positive and negative...but I'm not sure which wire to attach where?
Anyone dealt with this recently?
FOLLOW UP: Brown is Ground and Purple is Positive
Last edited by artguy; 01-18-2008 at 05:04 PM. Reason: Follow up.
not really sure but hope this helps.
http://bmwe34.net/e34main/maintenanc...MW%20525iT.pdf
HID 5000k low 3000k fogs
dynaudio seps. mc intosh amp
ACS w/yokohama advan sport tires
Race logic TractionControl
My rendering of the sending unit side of the connector (I re-wired it due to corrosion).
On mine, the "brown ?" at top left is (-), the "Large gr/vi" at top right is (+). You state you have a purple, so its either the same green/violet on mine or a different color. Just find the colors at these locations and they 'should' be the same when they emerge at the pump.
Hope it helps,
Dave M
10/90 Build 525im, 630,000+km, Eibach/Sachs, Engine Rebuild
*RIP Oskar the DOG *
...i think.... haven't seen a brown wire yet that isn't neg or ground either in diagrams or in my car. good rule of thumb maybe, unless you're playing with gasoline... then maybe you should be extra sure
...help me i'm freeeezing...
You wont get a job as an electrician in the UK - brown is industry standard for liveOriginally Posted by timandbim
So it's manufactured in the Czech Republic...do you think they follow the UK standard as well?Originally Posted by whiskychaser
heh- dude, i wouldn't get a job at a tea shop in the UK!Originally Posted by whiskychaser
but i'd like to know.... 'cause every brown wire i've seen on my car is either a common ground or a neg. i always double check with a schematics page, but that seems to be the case on my '89 at least.
What I think is that brown isnt always groundOriginally Posted by artguy
Originally Posted by bmwrp8
Question ? According to diagram on this file the fuel sander is fasten to the fuel tank but the fuel pump seems to be put completly loose in the bottom of the fuel tank, just connected to the sander plate by hoses (The Bentley does not show much more detail about that); is it really the case ? I must have miss something, could you explain plse.
As good as the Bentley is, it does lack things at times.Originally Posted by Claude
The fuel pump is attached to the fuel sending unit by two wires and two hoses. Here they are together:
In the tank the fuel pump sits in a cradle which is attached to the inside of the tank. Here is the cradle on the bottom of the tank:
And here is a picture of the pump installed in the cradle while still attached to the sending unit (Note the pump release tabs):
I just got these parts out last night. So now I will be able to tell which wire is positive and which is negative and post the solution to this original post soon.