[GearHead335i]

Have an n55 I just rebuilt from the ground up, all bearings rods and main, completely disassembled the head and put new roller bearings in on the eccentric motor, new cam bearings for eccentric and intake cam as they were worn, and a lot of other things. I finally got all the kinks worked out and as I am backing out of my driveway the wire for the oil level sensor was hanging too low, and I didn’t have the front driveshaft put in as it just kind of gets in the way when needing access from underneath, and the 4 bolts that hold the driveshaft to the diff were left there so I didn’t loose them. So the wire ends up getting yanked straight out of oil level sensor. The exposed wires must have touched each other or a piece of the subframe and shorted something bc the car was in reverse going backwards as they were ripped out of the plug and the car stops right in its tracks and almost basically pops itself in P and the car shuts off. Try to restart, no dice, went to run the codes and no communication with the dme. I can read other systems like

CAS- immobilizer bus fault

TCU- CED4 no message from engine management

A lot of others that all say no message from engine management.



I’m at a loss and I would love any suggestions you guys have.


Also getting several messages on iDrive as well;

[gbalthrop]

Originally Posted by GearHead335i

Have an n55... [NEED Last-7 Characters of VIN -- See Below] ... backing out of my driveway the wire for the oil level sensor was hanging too low... the wire ends up getting yanked straight out of oil level sensor. The exposed wires must have touched each other or a piece of the subframe and shorted something bc the car was in reverse going backwards as they were ripped out of the plug and the car stops right in its tracks and almost basically pops itself in P and the car shuts off. Try to restart, no dice, went to run the codes and no communication with the dme...

The OZS gets power directly from the DME. Lack of Scan Tool (& Other) Communication with DME suggest LACK of Power Supply to DME (Blown Power Supply Fuse after K6300 DME Main Relay). Without your VIN-7, I can't be sure what fuses are related to DME Power Supply. I'll attach 3/2011 N55 DME Supply ISTA SSP to next post. If that is correct for your N55, check fuses F11, F16, F37 & F38, all on JB Fuse Panel. If you need fuse Chart/ Locator, please advise.

I presume Starter Cranks but Engine does NOT fire?? If that is NOT correct, please advise.
George

[gbalthrop]

ISTA ScreenPrint, 3/2011 N55 DME Supply SSP, Fuses F11, F16, F37, F38, all on JB Fuse Panel, per prior post.
George

[GearHead335i]

Originally Posted by gbalthrop

ISTA ScreenPrint, 3/2011 N55 DME Supply SSP, Fuses F11, F16, F37, F38, all on JB Fuse Panel, per prior post.
George

Last 7 of vin: L989960

Yes car cranks m, no start.

[gbalthrop]

Originally Posted by GearHead335i

Last 7 of vin: L989960; Yes car cranks m, no start.

ISTA says that "VIN-7" is for 2012 X5, N55, AT.
Is THAT Correct?? Completely different power supply circuitry from E9x models.
George

[GearHead335i]

Originally Posted by gbalthrop

ISTA says that "VIN-7" is for 2012 X5, N55, AT.
Is THAT Correct?? Completely different power supply circuitry from E9x models.
George

Yes it’s an e70 x5 35i. The x forums get zero traction whatsoever.

[GearHead335i]

Don’t think this is the direct issue why the car currently isn’t firing off, I think there is some fuse or relay that is blown as a result of the oil level sensor wiring shorting out, but the car was also sitting for a long time before I rebuilt it. A period of almost 2 1/2 years and I was hesitant to check this as I know when you open up the DME, it never seals like the factory but I always had some suspicions that there was some water damage or something to the DME from it sitting for so long because the car was misfiring and there was times where I felt like I was chasing my tail because I literally had replaced and rebuilt everything. Lo and behold;

[gbalthrop]

Originally Posted by GearHead335i

Yes it’s an e70 x5 35i. The x forums get zero traction whatsoever.

Well, I can furnish the ISTA wiring diagrams, Attached, to NEXT Post. However, I'm NOT sure HOW to interpret the wiring diagram which is QUITE different from E9x Models, OTHER than N55 335i/xi.

I would begin by checking fuse F4, Location attached. The way I interpret the Diagram, CAS Module applies power to DME when Ignition turned on, and DME Activates the DME Main Relay (1), IF fuse F4 is intact.

If NO Scan Tool connection with DME, but it DOES connect to all OTHER Modules, then it would appear that there is lack of power supply to DME (1) for DME to connect to "Hub" and Scan Tool to connect to DME, & (2) for DME Main Relay to be activated and supply power to F01-F03. Testing F01, F02, F03 for voltage with Ignition ON would confirm that. I have NO IDEA what "non-replaceable" means in Fuse ID information. Must be related to "Made in SC".

Hope this "Gets you started". If you need more info, please let us know. When you post back, please include list of ALL Fault Codes in ALL Modules, if you can, along with Scan Tool/ Diagnostic Software used.
George

[gbalthrop]

ISTA ScreenPrints referenced in prior post attached, 2012 X5, N55.
George

[GearHead335i]

Originally Posted by gbalthrop

ISTA ScreenPrints referenced in prior post attached, 2012 X5, N55.
George

Ok I got the f01-f07 box removed and they say “non serviceable” bc you can’t get into the box to check the fuses lol. Although something is rattling around in there… I’m tempted to crack it open and see if this is our culprit.

[GearHead335i]

Also cleaned up the dme board

[GearHead335i]

Took apart ism (integrated supply module) and found a 15 amp fuse blown… hoping this is it!

[Daaaaaaaan]

DME board just looks like solder flux from soldering the through-hole parts. Nothing wrong with cleaning it off.

There was a trace near one of the through-hole soldered pins that looked a bit blackened though. Not sure if it’s just the picture.

[GearHead335i]

Replaced the fuse, got the dme back in and same situation. Crank no start with all the error messages and not able to connect to dme. I still have the oil level sensor not hooked up with the wires trimmed so it’s not exposed ( just to test to see if the 15a fuse fixed it) could the oil level sensor not being hooked up be why it’s still like that or did I maybe fry the integrated supply module and not just the 15amp fuse in there. Or is it the dme all bc there was a short with a sensor bmw had wired half way across the motor to get to it just waiting for something to happen.

[GearHead335i]

Hold up! Forgot one of the plugs on the ISM 🤦🏼*♂️🤦🏼*♂️🤦🏼*♂️ and we have power to the dme! Can check codes now! Going to put it back together and try to fire her up.

[gbalthrop]

Originally Posted by GearHead335i

Replaced the fuse, got the dme back in and same situation. Crank no start with all the error messages and not able to connect to dme...

Did you check fuse F4? The SIX wires from the fuse Module (Connector X60181) you show in photos 1 & 2 of post #10 should be Red/Green for Pins 1,2,3,5,6 & White/Gray for Pin #4. There SHOULD be battery Voltage at ALL Red/Green wires with Ignition ON. You could stick a pin/needle in the Red/Green wires to test for K6300 (DME Main Relay) operation.
George

[GearHead335i]

Does anyone have the wiring diagram for the oil level sensor? The wires got pulled clean out so i don’t know which go where. I’ve got a solid purple that I’m 95% sure it goes in pin one because that was the only one that had a little bit of the wire still in place, a red with green stripes and black with white stripe.

1- solid purple
2- red with green stripe or black with white?
3- red with green stripe or black with white?

[GearHead335i]

Originally Posted by gbalthrop

Did you check fuse F4? The SIX wires from the fuse Module (Connector X60181) you show in photos 1 & 2 of post #10 should be Red/Green for Pins 1,2,3,5,6 & White/Gray for Pin #4. There SHOULD be battery Voltage at ALL Red/Green wires with Ignition ON. You could stick a pin/needle in the Red/Green wires to test for K6300 (DME Main Relay) operation.
George

I got it sorted, I forgot to plug in one of the ISM connectors, silly mistake. Looks like replacing the 15a did the trick. Now just need correct pin out for oil level sensor, can you access that in INPA? FYI fuse f4 looks like it’s always been good too.

[gbalthrop]

Originally Posted by GearHead335i

I got it sorted... Now just need correct pin out for oil level sensor...

OZS SSP Wiring Diagram & Lines ID, with X62540 Connector view are attached.
George

[GearHead335i]

Originally Posted by gbalthrop

OZS SSP Wiring Diagram & Lines ID, with X62540 Connector view are attached.
George

Appreciate these man! You have been a big help!

UPDATE- 9/17/23 - 10/17/23 - Car was sitting for about a month and there was an unusual amount of rain while parked. Long story short, I get in the car in drive it maybe 3 miles, stopped, put the car in park briefly, got out of the car, got back in, put it in drive to pull out into an intersection from a development and as I’m pulling out and hitting the gas, the car just dies. Middle of the road, pitch black at night, sitting halfway across the intersection right after a sharp turn, great.

Try and get the car restarted, although it’s doing all of the same symptoms that I had earlier in this thread before I took out the integrated supply module and found a blown fuse. I get under the car, put it in neutral, push it back and start to look into if your fuse has blown again or if maybe water got in. Unhook the battery and take a look at the ISM and sure enough the first plug I pull out is filled completely with water…

Here’s the strange (could be bad) part, none of the fuses on the ism were blown. Still I swapped it with a new (not oem) ism, try and start it same result.

Also have NO COMMUNICATION WITH THE DME.

So far I have;

-Replaced ism with new (not oem) have an oem one on order.
-checked all grounds as well as did continuity test on engine to body and all is well. Also attached a temp ground (jumper cables) and tried to start, nothing, just cranks and cranks.
-checked all fuses in both front and rear fuse boxes, nothing blown.
-swamped the big black CAS fuse in the rear fuse box
- charged battery overnight and looks like it’s giving off 11.8 volt

Last thing is when I go and lock the car with the key the car doesn’t lock the passenger door. Also sometimes when I go to unlock it, I hit the unlock button and the alarm will actually start going off. Idk what the heck is going on but any help would be appreciated!

[GearHead335i]

Bump…charged battery up and still nothing. Looks like we are at 11.62 with ignition on and around 10.76 when cranking.

[e91Owner]

When you connect in ISTA, is the DME the only module that it can’t communicate to?