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How to Test your BMW EWS 3 before replacing it

Questions you may have:

  • How do I know if I need an EWS Kit?

  • Is this an EWS Issue or a Key Issue?

We always need to test the EWS3 First, remember the EWS system has a built in RELAY that basically just performs a U-Turn to your starter.

If you're vehicle has a EWS2 then please see these instructions instead: EWS2 Test

  • 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 / 25amp / 20amp max! Fuse into Pin 1 & 2 of the EWS3 Female plug (see picture below at very bottom). Remember, there is no way the fuse will not fit, if you are having trouble simply turn the plug around and it will go in.
  • 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 the engine is cranking go to Step 6. If the 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 Multi-meter is required)


PIN 9 = GROUND (All Models)


PIN 10 = +12V (Ignition OFF or ON)


PIN 11 = +12V (Ignition ON only) 


  •  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 R50 / R52 / R53 (S) EWS 3.3 Kit 05/2001 to 11/2006 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 +12V signal on PIN 2 EWS Female Plug then please GO-TO Step 9. If you are NOT getting a +12V to Pin 2 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 Connector -> If +12V is present Check +12V at Starter connector -> 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 Corroded Ground Wires. [IF YOU REACHED TO THIS STEP, THEN THE EWS DOES NOT NEED REPLACEMENT!]
  • Step 10: (You are Not getting a +12V signal from Pin 2) : Go back to your Ignition Switch and see if its producing a +12V signal -> If No +12v is Present -> 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.
  • Step 11: Replace Ignition Switch
  • Step 12: If ignition switch has no power -> Check fuses related to the ignition switch or broken wires or lose grounds etc.  [IF YOU REACHED TO THIS STEP, THEN THE EWS DOES NOT NEED REPLACEMENT!]


Note: RPM Motorsport is only trying to help the BMW community and takes no responsibility for you (the customer) damaging any components in your vehicle. Please get the help of an experienced BMW mechanic if you are not comfortable with performing the steps yourself.

EWS 3 Bypass

EWS Must be Removed for this Test!!! This is a EWS 3 Female Plug, Please insert a 30 amp fuse as shown in the picture.