E70 N63 DME Relay not picking up!

[BCX550I]

Hello out there! I am new to the forum, and have joined for probably the most common reason. My 2011 X5 50i would crank over, but not start the other day. I did a scan and the main codes that came up were 30BA and 30BB. I tested the circuits to the fuel injectors and then removed the DME to check the MOSFET's. Everything metered out good. Upon reinstallation of the DME I suddenly had a long list of codes, as well as my dash telling me of all the faulty systems. Turns out the DME wasn't powering up. I tested the DME relay, which passed with flying colours, but the wire that picks up the coils (White/brown) is not providing a solid ground to the coil. Would anyone have a wiring diagram so that I could trace out the ground issue, or faulty switching device? Thanks!

[Sophisticated Redneck]

Pm me for access to complete online wiring diagrams but before you dive too deep, I would double check all the bolts for the wiring harnesses that bolt it to the valve covers for the injectors/coils on both sides of the engine as they also serve as ground points. If all the wiring checks out, could very well be the MOSFETs are out according to those codes but I would be very suspect as to why it fried all of a sudden.

[BCX550I]

Thank you Sophisticated Redneck! My account is restricted for the time being and I am unable to send PM's. Double checking the wiring harness bolts is a great idea! I am on it! The ground issue I think I am having is on the switching circuit for the DME relay. When the car is off I have a full positive on the White/Brown wire, when the key is inserted and the Start button is pressed to switch the car "on" I get a slight decrease in voltage, but only enough to have a .5 voltage drop across the DME relay coil. I am thinking that either the device that is responsible for switching on the DME, or the ground point that the device is connected to is the culprit. I will PM you as soon as my account is no longer restricted, unless you have another method of communication that you are good with. Thanks!

[BCX550I]

I have discovered that the ground wire that switches the DME Relay goes into the DME. I am assuming this means that the DME turns itself on? Or possibly has a protection circuit to turn itself off? Either way I am not able to trace the circuit any further. Has anyone else had an issue when you have removed your DME for an inspection (with battery disconnected) and reinstalled it to find that it was not turning on, and you received a bunch of trouble codes of "no message"?

[Sophisticated Redneck]

Tried to send you a pm too but system won't allow. Post back up here with a email address I can contact you at. Leave out the .com so the spam bots don't find you

[DrVirz]

Howdy all.

Apologies to revive an old thread, but I too am having issues with the DME. Sometimes its alive, sometimes its dead!

I have ISTA however the version I have appears to have functional wiring diagrams missing.

Sophisticated Redneck, any chance I can be sent wiring diagrams? It would be much appreciated!

[DrVirz]

Howdy all,

Just reporting back, I managed to trace the DME issues to a bad ground from the DME compartment in the engine bay. No electrical issues now