[Runt]

This started overnight; drove into the garage fine, next morning: spin spin spin with nary a pop.
The most recent work on the car was several months and hundreds of miles back, fitting a replacement JBE to add Servotronic steering.

Short VIN: A951286
The battery is strong, and I have a high-amp battery charger hooked up in addition. Battery voltage is ~ 13.5
Ista+ connects to the ECM, and reports these codes: 2ACC 2ACB 2E85 6E24 5F77 A0B4
The Ista test plan goes first to the K6300 DME power relay, and basically says, "replace it". But I believe this relay is integral to the 'power distribution box' (fuse box) behind the glove compartment, and not separately replaceable. So I'd like to dig in a little farther before buying a new fuse box.

With the key in, ignition on, there's no voltage at Fuse37. That should be battery voltage, roughly, coming out of the K6300 relay.
=> so either the relay has failed, or it's not getting power+ground to activate it, or there's no power on the "input" side of the relay.

1. Looking at the power+ground to activate the relay first.
   1. Power I think comes from Fuse 4 through the ECU. Edit: nah, power to activate the relay comes from the large red cable going into the power distribution box.
   2. Ground I think comes from a red/gray wire coming out of the ECU.
      I back-pinned the connector in position 5 of the X6011 connector found in the white plastic DME box on the passenger side of the engine compartment. Then I grounded that pin. There was still no voltage out on Fuse 37.
      I read somewhere that power out of Fuse 4 into the ECM is required for the ECM to provide a ground signal. I checked Fuse 4; there is battery voltage available at its connections in the fuse box behind the glove box, and the fuse is good.
   3. I guess I'll hook the multimeter to that pin, and see if it goes to ground when the key is on? That would make me think the ECM was 'doing the right thing', that is: that the ECM is commanding the K6300 relay to activate. The next step... dunno.

Happy to have others' thoughts and advice here.
(the JBE error in that shot is due to me unplugging the air quality sensor from the area of the white plastic ECM box)

 

[Runt]

OP here. Am I wrong to try putting a sizable jumper (fused) from a Pin 30 source into the output of Fuse 37? This would simulate the closing of the K6300 relay.

 

[gbalthrop]

The DME Relay, K6300, SHOULD Power F37 (DME Supply), F38 & F39 when Ignition is ON. The DME is ALWAYS powered via F4, 10A fuse. When Ignition turned ON (Press START Button) DME SHOULD provide a Ground signal from X60005/13 (White/Gray wire) to X11010/1 (Pin #1 of Connector X11010 on upper-left of JB Fuse Panel). Most frequently-reported cause of NO DME Relay Activation is LACK of Ground signal, as opposed to JB or DME Relay malfunction.

The DME Relay is ALWAYS receiving B+ from the JB Power Cable, X13020 on the Right Side of the JB. So 1st check to see that you have 12V+ at that Large Red B+ Cable from the Battery. The Relay is "Activated" simply by applying Chassis Ground to X11010/1. So after confirming 12V+ at X13020, apply chassis ground to X11010/1, and listen for audible "Click" from DME Relay in JB. Do that test with Ignition OFF & quiet cabin.

If LACK of DME Relay Activation (Lack of Ground signal from DME) is the cause of "Crank, NO Start", then with Ground Jumper applied, you SHOULD be able to turn Ignition ON, and Start Engine. Please let us know what you find in those tests, and we can suggest "Next Steps" if needed (you sound like you already understand the situation correctly ;-)

Attached are ISTA ScreenPrints for clarification.
George

 

[Runt]

Thanks for that, @gbalthrop. Looks like I'm going to add to the 'Most frequently-reported cause' count.

With the ignition on, I applied chassis ground to X6011/5 (the other end of the red/gray wire that terminates at X11010/1). Now Fuse37 shows battery voltage, and the engine starts.
So I'm happy (well, happier) with the state of the K6300 DME power relay, but must go looking for the cause of "no ground signal" somewhere between the X6011 connector and the ECM. Or, I supposed, inside the ECM.

I'll move my chassis ground to the X6005/13 connector on the ECM itself, and repeat the voltage test at Fuse37. Assuming that gives a positive result... am I pulling the ECM next?

A thought: could a fault in ComfortAccess or the 'Immobilizer' system be convincing the ECM to withhold the ground signal? Or do those systems' contributions to startup happen prior to this stage?

 

[gbalthrop]

... I'll move my chassis ground to the X6005/13 connector on the ECM itself, and repeat the voltage test at Fuse37. Assuming that gives a positive result... am I pulling the ECM next? A thought: could a fault in ComfortAccess or the 'Immobilizer' system be convincing the ECM to withhold the ground signal?...

My approach would be a bit different, particularly if you still have the E-box open, for "convenient access" to X6011. Note that the White/Gray wire from X60005 goes to X6011/5 (Pin #5 of X6011 in E-box). So you can disconnect that connector and test for:
1) Ground Signal from X60005/13 via the White/Gray wire when Ignition ON (continuity to ground);
2) Apply a Chassis Ground to the Red/Gray wire that runs from X6011 to the JBE, X11010/1, and see if DME Relay is activated and engine will start.

It would appear that either (a) the DME is producing NO Ground signal at X60005/13 with Ignition ON, or (b) that ground signal is NOT getting sent to X11010/1. The tests described in 1 & 2 above are designed to determine which. We can then devise "next steps". Others have devised ways of "bridging" a defective pin at X60005/13 if it comes to that. Don't send off your DME for repair just yet.

And NO, I don't think this has anything to do with CA or Immobilizer (EWS4). If you can turn on Ignition without placing Remote Key in Insert Compartment (or unlock doors), then CA is working. If Immobilizer allowed "Hotwire" by simply applying Ground to X11010/1, then it would be "wasted".
George

 

[Runt]

Well, with the X6011 connector in the E-Box disconnected, ignition on:

• no continuity to ground on the X6011 receptacle pin that runs to to ECM connector/pin X6005/13.
• a chassis ground applied to the red/gray wire in the X6011/5 plug/pin does activate the K6300 DME power relay, and Fuse37 has battery voltage.

It's still possible that the wire between X6011/5 and X6005/13 is broken. I'll test it for continuity tomorrow (but everything inside the E-Box looks pretty nice thus far).
Otherwise... <points finger at ECM>

Thanks again for your detailed and logical suggestions.

 

[gbalthrop]

Well, with the X6011 connector in the E-Box disconnected, ignition on:

• no continuity to ground on the X6011 receptacle pin that runs to to ECM connector/pin X6005/13.
• a chassis ground applied to the red/gray wire in the X6011/5 plug/pin does activate the K6300 DME power relay, and Fuse37 has battery voltage.

It's still possible that the wire between X6011/5 and X6005/13 is broken. I'll test it for continuity tomorrow (but everything inside the E-Box looks pretty nice thus far).
Otherwise... <points finger at ECM>

Thanks again for your detailed and logical suggestions.

 

[gbalthrop]

Round 3:
Before beginning "Round 3", just a brief summary of where we are, and how we got here, so everyone is on the same page:
1) Car is 2012 328xi N52 E91, which overnight developed "Crank, NO Start", with fault codes for DME Relay Activation, and NO voltage at F37, which is fuse powered via DME Relay, that provides Main Voltage Supply to the DME Module on ALL 2008 & later E9x models. On E9x models built after 3/1/2007, that DME Relay is NOT a "Plug-in" relay, but rather soldered to the JB Fuse Panel Printed Circuit Board (PCB).
2) You tested Function of the DME Relay by applying a Chassis Ground Jumper to X11010/1, or Pin #1 of the Connector X11010, on the upper-left of the JB Fuse Panel. This caused the relay to "Click" or "Activate", providing power to F37 (and the DME), and also providing power to fuses F38 & F39 which provide power to engine components such as Injectors, Coils, and various Sensors.
3) You were then able to Start the Engine when Starter was cranked, as the DME, Coils, Injectors, and Sensors such as Crankshaft Sensor, Camshaft Sensors, etc. were NOW properly powered.
4) You tested for Continuity to Ground at the White/Gray wire from X60005/13 at the DME, testing at pin #5 of the intermediate Connector in the E-box, X6011/5. There was NO Ground signal or continuity to Ground with Ignition ON. There SHOULD have been such an "Ignition-switched Ground". You WERE able to apply a chassis ground jumper to the Red Gray wire running from X6011/5 to X11010 at the JB, and thereby Activate the DME Relay. You SHOULD do "Continuity Test" to rule out the last slim chance that there is a wire fault in the White/Gray wire between X6011/5 and X11010, and assuming NONE is found, proceed as described below.

All those tests indicate the DME Relay functions, is getting 12V+, but is NOT being activated by the Ground Signal that the DME SHOULD be sending from X60005/13 to X11010, to cause power to flow through the Relay Electromagnet, close/ "Pull-in" the relay contacts, and provide power to fuses F37, F38 & F39. So you have TWO choices:

1) Wire in a Toggle Switch to Manually Activate (and de-activate when turning engine off) the DME Relay by wiring-in a Chassis Ground Jumper completed by toggle switch, "T'd" into the Red/Gray wire at X11010/1. Although this is the quickest & easiest way to restore engine operation, it requires mounting such a toggle switch somewhere, and remembering to use it. It has the advantage of being a "One-Off Immobilizer" or Theft-deterrent, and the disadvantage of having to remember to turn it on/off, and the NON-BMW appearance.

2) Restore original function by doing one of the following:
a) Remove the DME, disconnect & open Module 5, and examine X60005/13 pin and connector socket for any obvious issue such as "spread socket", broken/ cracked Pin #13, solder failure where pin attaches to PCB, etc. You could test the Module "in situ", without removing it from the vehicle, and see WHERE on the PCB (how close to Pin #13) there is continuity to Chassis Ground when Ignition is turned ON. Remember, DME switches a GROUND signal when Ignition is ON.
b) If a switched Ground signal at or near Pin #13 is identified, then you can either:
(i) Repair,/ have an electronics shop repair, whatever is causing the open circuit between the Board & Pin#13, or
(ii) If Pin #13 is physically BROKEN or irreparable, you can solder a "Jumper" to Pin#12 which is adjacent to Pin #13. Pin #12 is NOT used on any MSV70, MSV80 (your DME), MSD80 that I have seen a Pinout for, and is clearly "NOT used" on your 2012 328xi per the attached Pinout. You do a jumper at the DME Pins, AND a Jumper between Sockets 12 & 13 in the Connector and normal function is restored. Several folks have reported success doing that. I have Personally NEVER OPENED my E-Box.

Hope to learn something from your efforts. Photos would be helpful to the rest of us.
George

 

[Runt]

First, the remaining facts:

• there is continuity all the way between X6005/13 (at the ECM plug) to X11010/1 (plug at the power distribution ("fuse box") behind the glovebox).
• there is continuity between X6005/13 (the pin itself, in the ECM receptacle) and the 'tie point' on the ECM printed circuit board (PCB).

Those two leave our fingers pointing at the ECM itself, somewhere "upstream" of that tie point on the PCB. The pins in the ECM receptacle look perfect.

I'm not (myself) going to go further in the ECM, as I'm simply not qualified to repair ... whatever is wonky. I'm evaluating options for professional repair of ECM, or procuring a new replacement ECM (with all the attendant synchronizing with the EWS)...

Second, I thought of an alternate version of the 'toggle switch' fix, using an automatically triggered standalone relay:

1. The coil of the relay would be connected to chassis ground and to a power source near the X11010 connector that has BAT+ when the ignition is on.
2. The "input side" of the relay would also be connected to chassis ground.
3. The "output side" of the relay would be tee'd into X11010/1 (the red/gray wire that the ECM grounds to activate ("close") the K6300 DME power relay).

Then, when the ignition is on, the standalone relay will activate, and make a connection between chassis ground and X11010/1 (similarly to the ECM's own action).

Third, some pictures of the E-Box, ECM connectors, & similar in the next post.

 

[Runt]

Pictures of the E-Box, ECM, and some connectors.

 

[Runt]

Fixed! (maybe)

So I put the sheetmetal cover back on the ECM, sprayed electrical cleaner on the pins & plugs of everything in the E-Box, re-installed the ECM and all the other connectors in there, and hooked up the battery.

Meanwhile, my local independent BMW repair shop called with an idea, which (very roughly) goes like this:

A 'bit serial data' bus connects a number of components in the car, including some components implicated in the error codes posted above. It is possible to re-set (or did he say, "take down"?) the BSD bus by un-plugging the Intelligent Battery Sensor (a small connector on the negative battery terminal).

I unplugged the IBS. The car started. Great! However... when I shut it off and plugged the IBS back in, it also started. So it's not a smoking gun yet.
I'm going to clear the codes and do some driving, expecting that some codes will reappear.

 

[gbalthrop]

Fixed! (maybe)
I unplugged the IBS. The car started. Great! However... when I shut it off and plugged the IBS back in, it also started. So it's not a smoking gun yet. I'm going to clear the codes and do some driving, expecting that some codes will reappear.

DIG your idea about Ignition-Activated Ground provided by relay! I suppose that is basically what the DME does to produce Ground at X60005/13: Ignition-switched Ground. (1) Simplest location of B+ Ignition-switched power source and (2) Relay Mounting component & location (easily available) would solve the puzzle.

Unless I missed something, the 2E85 BSD signal between DME & Coolant Pump was the only fault code you had related to BSD/IBS. We may NEVER know what caused the LACK of Ground Signal between X60005/13 & X11010/1, but since you found NO fault at Pin #13 of X60005 or its mounting to PCB of DME Module 5, I have to wonder about Connector X6011.

I did NOT completely understand your description of ALL conditions when you tested for Ground signal at X60005/13 & upstream in DME PCB, but it's THERE NOW! Was X6011 plugged in then, and Ignition ON? Keep in mind that the Voltage from F4 (KL30) ALSO passes through X6011, on its way to powering the DME control circuit at ALL times, so if X6011 is disconnected, DME CANNOT "Turn itself on".

Also of course, the Ground signal generated by the DME at X60005/13 when ignition switched on, has to pass through X6011, making the pins, sockets & wires of X6011 the SECOND most likely suspect after Pin #13 of X60005. At least that's my "Armchair Quarterback Story", and I'm sticking to it.

I'm NOT aware of any connection between the IBS and the DME Activation of K6300. If you come up with any wiring diagram info (or anything else) that suggests such a connection, please advise. Thanks for taking the time to attach photos and very detailed info on the tests you conducted.
George