How to fix BMW 335xi water pump failure with INPA?

I have 2008 335xi- N54, I am experiencing a 2acb/2acc on my 335xi which has the same JB layout. I’m seriously thinking of replacing the JB and hopefully that fixes it.

I did have some water damage due to a water pump failure that got coolant in the ECM box. No blown fuse or corrosion so it’s down to the the JB or DME.

Symptom and car info:
1) 2008 335xi- N54
2)I have access to MHD and BimmerGeeks ProTool
3) I currently do not have access to a multi-meter, have one at work but our state is under a Shelter-In-Place order so I can’t really leave the house.
4) The engine will CRANK but NO START,
-Water pump was replaced and verified functioning
-wipe and dry out the coolant from the ECM box
-removed the JB4
-check for corroded and wet connector pins, no corrosion but I noticed a little moisture inside the left DME connector, dry out the pins and wipe the female connector, put all connectors back to stock with JB4 harness completely removed
-flashed DME back to stock BIN
-Checked all fuses in fuse box 3x times (no blown fuses),
-Replace the I01068 black relay after being told that was the DME relay.

6) Whether any codes OTHER than 2ACB & 2ACC; Those are primarily the only two codes I get consistently, I ran several code check throughout each start attempt, here are the last two:

2E85 – BSD message, electric coolant pump: missing

2CFB DME, Throttle-valve adaptation value (this may be caused by me pressing the throttle during start up)
2D09 DME Throttle (this may be caused by me pressing the throttle during start up)
2E85 – BSD message, electric coolant pump: missing

A little back story on how this all happened. My water pump failed and overheat the car. Coolant oversprayed the engine bay and got into my ECM box (did not know this until after the fact). Initially, the car ran normally after the water pump and battery was replaced. The next day, the car would only crank but not start. I start experiencing random electrical issues, first the JB4 would no longer connect, the board was replaced and again the car started up immediately. Then as I had the car off and updating some settings in the the app, it lost connection and random clicks of various electrical systems were turning on/off.

I was then told to remove the JB4 completely and flash my custom tune back to stock via MHD. In the mist of flashing, the MHD app lost connection and no longer connecting to either MHD or Protools. Another round of search brought me to a coder who did a DME recovery for me. Now I am again able to connect via MHD/ProTools. This is where I am now. So please feel free to have me try anything, I’m not super skilled with electrical diagnostics but am very mechanically inclined so bear with me.


To restate the observations from the prior post:
1) It appears that the DME Relay is NOT being activated
2) If DME is NOT activated, the dashboard lights as normal when turning ignition ON, Radio, Blower, Wipers, Windows, Seats, and Starter all work as normal, BUT
3) The Engine will NOT fire, as the Sensors (Crankshaft & Camshaft) that time the DME pulse of Spark & Injectors are NOT powered, and the DME itself cannot function. Also, the LP Fuel Pump does NOT run. It still has Power Supply to the DME sufficient to have a Scan Tool connect & read Memory.

So the two recurring codes indicate, consistent with the symptoms you describe, that your DME Relay (K6300 on the TIS schematic linked in the prior thread, which happens to be the correct Schematic for your 2008 335xi with N54) is NOT being activated to Supply Power to general DME functions, and to power the Sensors mentioned above.

Proper Diagnostics would suggest that you use a Multimeter (OR a test light would also work) to CONFIRM that the DME Relay is NOT being activated. Here are wiring diagrams, Installation Locations, and Connector Views to help you determine WHAT is NOT getting Power Supply (12V+ on multimeter or test light).

Here is the wiring diagram that shows how the DME is always powered by the 10 Amp fuse F4. I would begin by using a multimeter or test light to confirm power at ONE of the two F4 sockets with the fuse removed. That is Battery power (NOTE the “30” above the fuse symbol indicating “Terminal 30” or Battery [unswitched] power).

F4 ONLY supplies control system power, and NOT power for other DME functions. NOTE that the DME “turns itself on” in that the Red/Gray wire from Pin #13 of Connector X60005 of the DME provides a ground signal to the K6300 DME Relay electromagnet. NOTE that Red/Gray wire passes through Pin #5 of Connector X60551 on the way from the DME to the Relay. That Connector X60551 is in the E-box as shown below, and that is the easiest location to test, particularly since you have the E-box open.

The 12V+ side of the relay electromagnet coil, and the other side of the contacts are BOTH ALWAYS powered by Battery power, or “Terminal 30”, also known as Kl.30 (Klemmen is German word for Terminal), so if you apply a ground to that Red/Gray wire, the relay should “CLICK” if it still works, and the engine should fire when the Starter cranks the engine. Here is a more complicated schematic of the Junction Box, which shows ALL of the relays & fuses. What is important here for YOUR understanding is Kl.30 (Terminal 30 or Battery Power), Kl.87 (Terminal 87 powered by operation of K6300 DME Relay, and K6300 itself, and WHY its operation is important.…ule/1VnXpW4emV

Even if you don’t have a multimeter or test light to check for 12V+ (in reference to Chassis Ground), you can STILL do a test to determine if the K6300 DME Relay works. What you have to do is apply a ground (any wire or conductor contacting good chassis ground) to the Red/Gray wire. There are several ways you can do that. The simplest is to locate the Red/Gray wire and stick a pin in it (penetrate the insulation and contact the wire inside), and then ground the pin. If you hear the relay click (located INSIDE the JB just above the Terminal 30g relay you replaced), then you have found the CAUSE of your problem (but you STILL have to locate the reason for NO ground signal & correct it). A corroded Connector Pin at the DME, at the JB, OR at X60551 itself, are the most likely causes if the Relay clicks when ground applied.

A more elegant way to ground the Red/Gray wire is to locate that wire inside the E-box, at Pin #5 of Connector X60551. Here is the TIS Installation Location for those two connectors, each at rear of E-box:

Since you got coolant in the E-box, that Connector, or moisture in the DME itself, are the most likely causes of your issue.

I would suggest reviewing the above so that you understand how to Activate/test the relay and then try that & let us know what you find. So you can understand WHY operation of that relay is necessary, here are circuits for Fuse 39 (Ignition coils), Fuse 37 (Camshaft Sensors), and Fuse 11 (Crankshaft Sensor), ALL of which are powered from Terminal 87, powered by the DME Relay (K6300):

I’m NOT familiar with ProTool, but if it can do most of the things INPA can do, you MAY be able to quickly determine if Terminal 87 (KL.87) is active or not when ignition is ON, just by connecting to the DME (MSD80 for your N54) and reading the voltage that way.

INPA is “Factory Level” software developed by the German-speaking guys who designed & built our BMW’s, so one would expect that if they found a way to display or control component data/function, ProTool COULD be designed to do the same. It’s just a matter of WHAT particular functions BimmerGeeks has developed to date.

With INPA, one can see KL.87 voltage displayed on a Status screen, as shown in the first bar graph on the top left of the 1st attached jpg. OR one can turn KL.87 on/off by activating or deactivating the DME Main Relay, as shown in the 2nd attached jpg. I have translated (in red) the pertinent parts of the German “Labeling” in those two screens. INPA allows a knowledgeable user to quickly conduct MANY tests that would require one to identify and access a particular connector, and “Backprobe” a connector or otherwise use a multimeter to measure voltage, continuity, resistance, etc. You can do all this just by connecting the laptop to the OBD II Socket and seeing the data, and/or controlling the component, on your computer screen. You just have to know what data can be viewed, and what screen to use to view it, or to control a component.

Keep in mind that the DME supplies a ground signal to the DME Relay to complete the Relay’s electromagnet coil circuit and close the relay contacts. The reason it is called “Terminal 87” is that Terminal or Pin #87 of a standard automotive relay is the Power Supply Terminal when the relay contacts are CLOSED, and Terminal 30 of that relay is Battery Power, to which Terminal 87 is connected when the contacts close.

I don’t know WHAT Documentation, instructions, or List of Functions ProTool has, or what support BimmerGeeks provides. I would encourage you (and anyone using ProTool) to share such information. ANY decent Scan Tool, or Diagnostic Software, is capable of doing a LOT more than just reading Fault Codes. It should also have the capability to (1) Read Parameters or input values such as Sensor signals or various voltage values, AND (2) Allow Activation of motors, valves, relays, etc.

The DME can only activate the DME Relay IF connections are intact between Pin #13 of Connector X60005 and the Relay coil, AND the DME is operational. Please let us know WHAT you are able to determine ProTool can do to (1) display Terminal 87 Voltage, and/or (2) Activate the DME Relay to power Terminal 87.

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Reply from the issuer:

I completely spaced out that I have INPA installed on my laptop. I’m not verse with INPA navigation but I was able to locate the kl.87 activation via Component Triggering > Actuator activation 1 > Clamp 87/mail relay DME. However, once I got into this section and attempt to turn ON, I get what appears to be an initialization error/ no component response error as seen below. After attempting this, my LPFP is now running constantly. Disconnected and cycled the ignition and LPFP is quiet again.

I also located the MWB1 and was also getting the same initialization error, second screenshot.

Upon additional research, with the cable that I had, I found that I had to modify the ediabas.ini file and update the port from 3000 to 6801. Once I did that, I was able to connect to the LIVE DATA portion and display the MWB1, see 3rd screenshot, it does not look like my KL.87 is getting any voltage. I also attempted to activate the relay but after trying to turn it ON, it errors out ultimately with NO RESPONSE FROM CONTROL UNIT.

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Further advice:

Good job getting the INPA data. I assume Ignition was ON when those screens were saved, and if so, that confirms that the DME is NOT “turning itself on” by activating the DME Main Relay (K6300) to power Terminal 87 (0.2V won’t cut it ;-). That explains “Crank but NO Start/Fire”, but we still don’t know if the relay is bad, there is a wiring fault in the “Activation ground wire (Red/Gray wire) and its connectors, or if there is an issue with the DME.

If I were dealing with that situation, my next step would be to try to apply a ground to the Red/Gray wire inside the E-box, at Pin #5 of Connector X60551. Here is the TIS Installation Location for that connector, at rear of E-box:


Here is the wiring diagram showing the Red/Gray wire from Pin #13 of Connector X60005 of the DME to Pin #5 of X60551. That wire NEVER leaves the E-box. THEN there is another Red/Gray wire from Pin #5 of X60551 (same size & color wire) that goes OUT of the E-box to the chassis wiring harness that runs to the JB (Junction Box) Connector X11010. It is THAT wire going to the JB to which you want to apply a ground (at Pin #5 of connector X60551 in the E-box):

I’ve never had to open my E-box, so I can’t provide any more tips than that, but hopefully the TIS wiring diagram and “Installation Location” are sufficient to solve the puzzle. I did test the DME Main Relay Activation function on my MSV80 DME, 328xi today. With radio off & quiet cabin, I could hear a low level “click” from the JB area when activating the relay, and the voltage value went from 0 to 12.2 when KL.87 was active. So hopefully when you apply ground to Pin #5 of X60551:
1) You will hear a click from the JB;
2) See 12+ Volts Value in KL.87 bar graph using INPA Messwertblock 1;
3) Have engine fire when Starter is cranked (OK to leave ground applied for that purpose, but disconnect it AFTER test Start & engine shutdown).
4) Be aware that there MAY be some short within the E-box given the history of coolant ingress, so be ready to remove jumper if any sparking, etc.
5) If you have NOT already done so, I would recommend thorough inspection of the DME and all components in the E-box, with use of a heat gun, heat lamp, or at least incandescent light bulb for radiant heat for 12 to 24 hours (to evaporate moisture), along with disconnection & inspection of connector pins & sockets, particularly X60005. Use Electronic Contact Cleaner to clean pins/ sockets if any corrosion is found. Water-damaged electronics can OFTEN be “resuscitated” by thorough drying and cleaning.

Reply from the issuer:

Okay, I think we are getting somewhere!

I have some wiring logic backwards but I have this figured out. I was able to find continuity on the WHITE/GREY wire!

Here are the results:
1. X60005 female connector Pin #13 goes to the X60551 FEMALE connector Pin #5 which is also WHITE/GREY. I was testing the male side of the X60551 connector thinking that wire never leaves the E-Box but that is not correct. The WHITE/GREY wire travels out of the E-BOX and comes back into the FEMALE connector of the X60551. See pics.

2. The WHITE/GREY wire continues on the male side of the X60005 connector Pin #5 and it actually loops into the X6011 male connector at Pin #5 then from there it changes wiring color to RED/GREY!! Sneaky! I’ve verified it by testing continuity from X60005 pin 13 to X6011 Pin #5 on the male side, just before it switches to RED/GREY.

So at this point, I think I am ready to apply ground.

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To simply test the DME Main Relay (K6300) to see if it functions, ALL you have to do is apply a ground, EITHER at X11010/Pin#1, OR at X60551/Pin#5 (latter assuming continuity between X60551 & X11010 ;-). Since the Relay coil is powered by Terminal 30 (Battery Power), you do NOT need ignition ON. If you get voltage at one of the sockets for fuse F37, then the relay is working (click is optional ;-). Here is F37 & K6300 circuit, simplified:


I have read your last post, and what I would suggest is to FIRST test for operation of the Relay ONLY, as described above. Do this with X60005 disconnected from the DME & Ignition OFF. IF you get relay click and 12V+ at F37, when you do this, then remove ground jumper, reconnect X60005 and all OTHER disconnected Connectors, and then apply ground at X60551/Pin#5, check for 12V+ at terminal 87 using INPA, and if good to go, Crank the Starter & see if it fires.


Finally, The car is alive!!!

Seriously have no idea how and what I did that I didn’t do before.

I plugged all of the connectors back on the JB/JBE. Hooked up and tested the DME Relay, had my wife touch the ground as I was literally in front of the JB. Heard the click several times confirming the location of the sound. It was definitely the K6300 clicking.

Next, plug the DME back in and opened INPA. Load the LIVE Data > MWB1 and instantly saw voltage on the KL87. I was like, no f**ing way, hit the start button and it started right up!!

Ran the codes, which still showed 2ACB/2ACC along with a bunch of other codes. I went ahead and clear them an now no codes!! I’m so happy and yet so dumbfounded on why it didn’t start when I replaced the DME and now it does. Only thing was maybe re-seating an assortment of connectors and fuses fixed it.

Credits to @Ov3rrun and @gbalthrop

Best inpa cable only 18usd: