How to Test your BMW EWS 3 before replacing it

Questions you may have :

  • How do i know if i need a EWS kit or a Key set if my car stopped cranking?

  • Is this an EWS Issue or a Key Issue?

We always need to Test the EWS First, remember the EWS system has a built in RELAY that basically just performs a U Turn to your starter. Lets first Locate your EWS since most models are different, you can click EWS Locations and you will find BMW and Mini Cooper EWS locations.

  • Step 1: Make sure that your car does Not Crank (Engine Doesn't Turn Over).
  • Step 2: Remove your EWS3 Unit and put it on the passenger seat so you don't forget its location.
  • Step 3: Insert a 30amp / 25 amp / 20 amp max! Fuse into Pin 1 & 2 into the EWS3 Female plug (See Picture Below at very buttom). Remember there is No way the fuse will not fit, if you are having trouble simply turn the plug around and you will be fine.
  • Step 4: Try to Start the Engine, we are looking for a Crank only, the Engine will never run, however all we need at this point is to get the engine to turn over.
  • Step 5: If Engine is Cranking go to Step 6 , If Engine is still Not Cranking go to Step 8.
  • Step 6:  Since the Engine is Cranking we need to do one last step. Please Check the Pins of the EWS FEMALE PLUG (We do not use colors, only PIN numbers) (Test Light or Multimeter is required)


PIN 9 = GROUND (All Models)


PIN 10 = +12V (Ignition OFF or ON) (Mini Cooper Fuse F24) (E46 3 Series Fuse F67) (E38 7 Series Fuse F26) (E39 5 Series Fuse F12) (X3 Fuse F67) (X5 Fuse F11) (Z4 Fuse F10) (Z8 Fuse F16)


PIN 11 = +12V (Ignition ON only) (Mini Cooper Fuse F6) (E46 3 Series Fuse F14) (E38 7 Series Fuse F44) (E39 5 Series Fuse F37) (X3 Fuse F14) (X5 Fuse F39) (Z4 Fuse F12) (Z8 Fuse F27)


  •  Step 7: If Step 4 & 6 are completed and ALL is OK then you need to send over your EWS with all your keys and order a BMW EWS 3.2 KIT (01/1997 to 03/1998) OR BMW EWS 3.3 KIT (03/1998 to 05/2006) or Mini Cooper EWS KIT from our online store.
  • Step 8: (Engine Still Does Not Crank) You will need to make sure that Pin 2 (EWS Female Plug) is getting a +12V. If you are getting a +12Vsignal on PIN 2 EWS Female Plug then please GO-TO Step 9. If you are NOT getting a +12V to Pin2 on the EWS Female plug then please GO-TO Step 10.
  • Step 9: (You are getting +12V from pin 2 in the EWS Female Plug ) : Check Pin 1 for +12 to insure that your Fuse is OK -> if +12v is present Check Engine Connecter -> If +12V is present Check +12V at Starter connecter -> If +12V is Present Change you must change your Starter -> If +12V is NOT Present Repeat the process of Step 9 by checking Broken Lines or Wires.
  • Step 10: (You are Not getting a +12V signal from pin2) : Go back to your Ignition Switch and see if its producing a +12V signal ----> If no +12vis coming out ----> Check if ignition switch has power. (All Solid RED Wires should have Power). ---> IF there is +12V GO-TO Step 11. If there is NO +12V on the RED solid wires GO-TO Step 12.
  • Step11: Replace Ignition Switch
  • Step12: If ignition switch has no power --> Check fuses, broken wires etc.




RPM MOTORSPORT LTD. Is only trying to help the BMW community and take no responsibility for You (The Customer) damaging any components in your vehicle, please make sure you have some kind of background in the BMW World before going deep into this.