[overbo0st]

I want to preface this with saying I have been researching this issue and so far been able to trace the issue to the terminal 30g relay in the glovebox.

Car-
2011 335d (stock), 80k miles.

Backstory-
Last week I went to start my car and it wouldn't start, all electronics worked besides folding mirrors, trunk light, glovebox light, HVAC, iDrive, maybe a few that I didn't notice. Wipers turned on and wouldn't go off...gauge cluster had TPMS sensor warning, transmission warning, ABS warning, check engine, etc. Wouldn't allow me to shift out of Park. It recognized the key in the slot but wouldn't turn over. Tried the spare key and it didn't change anything. After some quick searching I found the common cause being the terminal 30g relay in the glovebox. Pulled mine out, put it back in and the car fired up just fine. No warning lights or anything abnormal. I figured my relay was going out so I replaced it with a brand new OEM unit. That was last week Wednesday.

Fast forward to yesterday, Monday, on my lunch break I go to start the car and the issue has returned. I remedy it by removing the relay and plugging it back in, car fires up. I thought it might be corrosion and maybe the pin/slots have areas of no contact between them, but no matter how far I insert the relay, even with it BARELY in, it seems to make contact and the car fires up. I bought some di-electric grease to apply to the pins just to cover that in case.

I am a bit confused as to what would cause the relay to either intermittently work or maybe something isn't sending it power when it should?

Next steps-
I am borrowing a code reader from my friend to see if anything is stored in the ECU from when it doesn't start. I really don't want to go down the rabbit hole of throwing money at the car with new parts that may or may not solve my issue. My list of culprits is
-JBM
-CAS module
-Key holder module
-Battery (though I think if this was the case I'd also see other issues...electronics as a whole intermittently working, hard starts, etc.)

Has anyone had this strange issue happen to them or have a good place where I should be looking for the root cause? Thanks!

[marvinstockman]

You need to see if you're getting 12 volts to the starter solenoid. You'll need an extra person and a voltmeter.

Also, you could have worn starter brushes. Next time bang on the starter with a hefty broomstick.

[dpaul]

Originally Posted by marvinstockman

You need to see if you're getting 12 volts to the starter solenoid. You'll need an extra person and a voltmeter.

Also, you could have worn starter brushes. Next time bang on the starter with a hefty broomstick.

This has nothing to do with the starter. The OP saw a classic sign of low voltage - wipers that go on and don't turn off - and physical manipulation of the relay providing power to terminal 30g restored (temporarily) the ability to start the car. Starter could not possibly be responsible for those symptoms.

OP - have you had the battery cable recall performed? The symptoms don't fit perfectly but there is some similarity.

https://www.e90post.com/forums/attac...1&d=1364258411

[gbalthrop]

Originally Posted by overbo0st

...2011 335d...the issue has returned. I remedy it by removing the relay and plugging it back in, car fires up...I am a bit confused as to what would cause the relay to either intermittently work or maybe something isn't sending it power when it should? [BINGO! ]
Next steps-
I am borrowing a code reader from my friend to see if anything is stored in the ECU from when it doesn't start...

Since removing & reinserting the 30g relay allows start signal to be sent to starter (and otherwise normal operation), first SWAG is corroded contacts in Relay Socket on JB. Try some Electronic Contact Cleaner & inspect with bright light & magnification. BTW, was your car subject to Blower Motor Harness recall & has that been done? MAY be related.

Please provide jpg files of any Fault Code Readout: Codes, Freeze Frame Data, Definitions & Details. Your Kl.30g Relay (Terminal 30g Relay), aka "IO1068" in TIS circuit diagrams, is controlled by a signal from the CAS per this diagram:
https://www.newtis.info/tisv2/a/en/e...system/uXuCNh9

That diagram does NOT show it, but the CAS operates the Terminal 30g Relay by sending 12V+ to the COIL of the relay electromagnet, per this complicated schematic showing Terminal 30g at the BOTTOM of the page:
https://www.newtis.info/tisv2/a/en/e...ule/1VnXpW4emV

I would suggest checking the two Connectors involved:
1) X11010 at upper-left of JB;
2) X13376 at the CAS;
per these two TIS "Installation Locations":
https://www.newtis.info/tisv2/a/en/e90-335d-lim/RKy9OeU
https://www.newtis.info/tisv2/a/en/e90-335d-lim/RKNic75

If you need any help using the TIS interactive schematics, let us know.

George

[overbo0st]

Thanks for the replies guys.

1. I checked the open recall BMW site and nothing comes up for my vehicle, so I'm guessing any recalls have been performed. I purchased the vehicle just over a year ago and under my ownership I've only performed routine maintenance on it.

2. Once I get a hold of my friend's diagnostic tools I'll pull reports and look for that specific info. He won't be back in town for a week but I will be sure to follow up, even if resolved, to help anyone in the future who may experience this.

[gbalthrop]

Originally Posted by overbo0st

...I checked the open recall BMW site and nothing comes up for my vehicle, so I'm guessing any recalls have been performed. I purchased the vehicle just over a year ago and under my ownership I've only performed routine maintenance on it...

I wasn't clear in my suggestion of how recall performance might be related to your issue. The recall was NOT intended to remedy anything related to your issue. IF it WERE Performed, it COULD have led to an issue with the signal from the CAS to the Kl.30g Relay however.

NOTE on page 7 of the attached RCRIT pdf that Connector (1) from the CAS to JB has to be removed as a preliminary step to removal of the entire JB as shown in subsequent photos. My only thought is: "Recalls may have unintended consequences", and knowing what procedure are actually performed on your vehicle MAY be helpful. NOT suggesting BMW dealer Tech that performed this procedure (if applicable) did anything wrong. Simply pointing out someone may have done Disassembly/ Reassembly there recently.

George

[gbalthrop]

Here is a better TIS schematic for CAS control of "IO1068" coil, or operation of Kl.30g Relay on JB:
https://www.newtis.info/tisv2/a/en/e...inals/AFwcvDyX

George

[overbo0st]

Originally Posted by gbalthrop

I wasn't clear in my suggestion of how recall performance might be related to your issue. The recall was NOT intended to remedy anything related to your issue. IF it WERE Performed, it COULD have led to an issue with the signal from the CAS to the Kl.30g Relay however.

NOTE on page 7 of the attached RCRIT pdf that Connector (1) from the CAS to JB has to be removed as a preliminary step to removal of the entire JB as shown in subsequent photos. My only thought is: "Recalls may have unintended consequences", and knowing what procedure are actually performed on your vehicle MAY be helpful. NOT suggesting BMW dealer Tech that performed this procedure (if applicable) did anything wrong. Simply pointing out someone may have done Disassembly/ Reassembly there recently.

George

Ahh gotcha I see. If this recall was performed prior to my ownership, the car was operating perfectly fine for the past year (Purchased Oct 2018) and it wasn't until last week that this issue began. But good to know the proper procedure if I do need to remove the JB down the road for anything!

[icon2015]

When this issue occurs again, measure if you have 12V at pins 2 and 6 on X11010 connector in JBBF.
- If you do, then I suggest that you check if that battery cable recall was done, if it wasn't then do it, and also replace the Fuse box, as some times it is affected by that bad cable connection.
- If you any of them doesn't measure 12V then the CAS might have a problem. 15_JB line is activated when you enter the key, and 30G_JB is activated after you press the start button without pressing clutch/brake pedal.