Announcement

Collapse
No announcement yet.

How to wire E30 M3 oil temp gauge into 325i?

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

    How to wire E30 M3 oil temp gauge into 325i?

    Hi all,

    I have installed an E30 M3 instrument cluster into my 325is, and I'm having a lot of trouble getting the oil temp gauge to work. I have been basing my wiring on the diagram here http://www.sixinabox.com/oiltemp.pdf

    So what I did was splice into the green/white (+) and brown (earth) wires on the blue plug in the back of the cluster, and then ran a wire into the engine bay to use for the temp sender. Here's the thing, once I fire up the ignition the needle blasts straight to maxmimum, and stays their regardless of whether I ground the temp sender wire or not. Now it seems this was likely to happen because by the wiring diagram it has two earth connections (brown wire and temp sender)...?

    I'm really hoping someone else here has done this cluster swap and can tell me what they did. I'm confused!!!!

    Is the M3 sender a single post temp sender, or a dual post? Perhaps what is supposed to happen is that instead of earthing the sender wire, it's actually supposed to send back a +ve signal?

    Cheers,

    Andrew.

    #2
    Sounds like you have the earth and the wire to the sensor reversed. The M3 sensor is single post. Power goes into the gauge and is grounded through the sensor. The sensor vaires the ground connection which therefore raises or lowers the voltage allowed to pass thought the gauge which generates the reading.
    Adam Fogg- '88 M3

    Common sense- It's the new 'gifted'

    Comment


      #3
      Green Stripe is +12
      Brown Solid = Ground
      Brown Stripe = Signal, run that to the e30 m3 temp sender

      You have the browns reversed

      Comment


        #4
        Thanks guys...I'll give that a try.

        BTW...does anyone know how many ohms the sender is meant to be?...or should I just buy the M3 sender from BMW?

        Also...what's the story here: http://www.realoem.com/bmw/showparts...g=11&fg=30 The oil temp and pressure switches are the same thing on the diagram. What's that all about?

        Comment


          #5
          Originally posted by Drew325is
          Thanks guys...I'll give that a try.

          BTW...does anyone know how many ohms the sender is meant to be?...or should I just buy the M3 sender from BMW?

          Also...what's the story here: http://www.realoem.com/bmw/showparts...g=11&fg=30 The oil temp and pressure switches are the same thing on the diagram. What's that all about?
          I think that just means that a temp OR pressure switch could be installed in the same place.

          Comment

          Working...
          X