[CoKid]

First post here, coming from an E46, this seems to be a whole new world - be gentle!

As short as I can make it. I bought used 2008 328xi (N51) a couple weeks ago. It ran fine for two days, but on the 3rd day I experienced a crank but no start condition. I spent the better part of the day tracking it down to a loose ground strap on right side of engine. I tightened that up - everything seemed good, except for a bunch of codes, of course. The car came with a Foxwell NT510, and I used the "clear all" function, which took care of most of the codes, but since then, the lights have been going downhill fast - at this point, only a few lights are actually working. Among the remaining codes were several FRM codes:

9CB8 (Exhaustive discharge protection of battery deactivation, side-marker light)
9CB5 (Battery exhausted)
9CCF (Drive, pivoting, mirror driver side faulty)
9CBA (Comm LIN unit disturbed)
9CA9 (Terminal 30A connection faulty)

And a several others:

A559 Instrument Cluster: Power supply has been switched off (closed-circuit current cutoff relay)
A6CF JBE: AUC sensor
2AAC DME: Variable intake system 2, self-diagnosis
A387 TCU: Fault, Bluetooth aerial

So then this morning I cleared everything and ran another full scan, without starting the engine. That resulted in just these FRM codes: 9CB5 and 9CA9. Once I started the engine and ran scan again, it expanded to the full list of FRM codes above, plus the JBE code.

I've checked fuses as best I can. There appears to be a lot of variation on fuse blocks in that 2008 E90 time frame, and different diagrams show different fuses involved with the FRM, but at least all the 30A fuses (and one 40A) are good in my case. I also checked lamps in the headlight, turn, parking/brake units, they are all good.

One last thing - the Foxwell has an "Active Test" function, which I used on the FRM 30A terminal. It reported 0V, so I assume it's not getting power - somehow. Everything else showed good voltage.

In troubleshooting the no start, I did disconnect the battery, and connected a charger (under the hood) multiple times. Really hoping I didn't fry the FRM, but perhaps? Is there a definitive test for that?
Please, please E90 gurus - what does it all mean? I'M SO CONFUSED!

[dpaul]

Originally Posted by CoKid

First post here, coming from an E46, this seems to be a whole new world - be gentle!

As short as I can make it. I bought used 2008 328xi (N51) a couple weeks ago. It ran fine for two days, but on the 3rd day I experienced a crank but no start condition. I spent the better part of the day tracking it down to a loose ground strap on right side of engine. I tightened that up - everything seemed good, except for a bunch of codes, of course. The car came with a Foxwell NT510, and I used the "clear all" function, which took care of most of the codes, but since then, the lights have been going downhill fast - at this point, only a few lights are actually working. Among the remaining codes were several FRM codes:

9CB8 (Exhaustive discharge protection of battery deactivation, side-marker light)
9CB5 (Battery exhausted)
9CCF (Drive, pivoting, mirror driver side faulty)
9CBA (Comm LIN unit disturbed)
9CA9 (Terminal 30A connection faulty)

And a several others:

A559 Instrument Cluster: Power supply has been switched off (closed-circuit current cutoff relay)
A6CF JBE: AUC sensor
2AAC DME: Variable intake system 2, self-diagnosis
A387 TCU: Fault, Bluetooth aerial

So then this morning I cleared everything and ran another full scan, without starting the engine. That resulted in just these FRM codes: 9CB5 and 9CA9. Once I started the engine and ran scan again, it expanded to the full list of FRM codes above, plus the JBE code.

I've checked fuses as best I can. There appears to be a lot of variation on fuse blocks in that 2008 E90 time frame, and different diagrams show different fuses involved with the FRM, but at least all the 30A fuses (and one 40A) are good in my case. I also checked lamps in the headlight, turn, parking/brake units, they are all good.

One last thing - the Foxwell has an "Active Test" function, which I used on the FRM 30A terminal. It reported 0V, so I assume it's not getting power - somehow. Everything else showed good voltage.

In troubleshooting the no start, I did disconnect the battery, and connected a charger (under the hood) multiple times. Really hoping I didn't fry the FRM, but perhaps? Is there a definitive test for that?
Please, please E90 gurus - what does it all mean? I'M SO CONFUSED!

If your door locks, mirrors and windows still work you haven't bricked your FRM - actually just being able to retrieve error codes from it means it hasn't been destroyed.

Stupid as it sounds, be sure your battery is in good condition. These cars are quite sensitive and a dying battery can cause a raft of error codes that are not obviously related to one another.

Measure the battery voltage with the engine off. If it's 12v or higher, that's not the issue. The next thing would be to make sure you've actually tested the all the fuses related to the NFRM. My best guess is that there should be four fuses; two 30 amp and two 40 amp. If you provide the last 7 digits of your VIN, I can try to check their numbers/locations for you.

[F31B48]

I would say your battery needs replacing. As dpaul said, a good battery in these cars is crucial. If you keep running with a battery that is in poor condition it will lead to issues and headaches for you.
A559 Instrument Cluster: Power supply has been switched off (closed-circuit current cutoff relay)
9CB8 (Exhaustive discharge protection of battery deactivation, side-marker light)
9CB5 (Battery exhausted)
These codes are basically telling you the battery has been completely discharged (exhausted) The car has tried to shut down some of the electrical systems to try and stop the battery from becoming discharged (codes A559 and 9CB8)

I would suggest getting battery charged and tested by a professional with a proper battery tester, and obviously if it's bad replace it, then make sure it is registered to the car.

[CoKid]

Thanks to both of you! I will get the battery checked. I did check it with the Foxwell, and it indicated it was fairly new, but it did drain quicker than I thought it should when I was originally troubleshooting the no-start condition. I of course was running the starter many times in that effort (with adequate time between, I'm not THAT dumb), and I just attributed it to that. I did have to charge it at one point, but I charged it to what I thought was a full charge. But I'll get it to a shop - probably Monday - for a "professional" test.

Thanks again - good to know I (hopefully0 haven't pooched the FRM.

[colorado.e9x]

Welcome to E90 ownership

A6CF JBE: AUC sensor
Fix: Replace it

2AAC DME: Variable intake system 2, self-diagnosis
Fix: Rebuild or replace small DISA valve (you only have one)

Also I believe the N51 has some crazy emissions bullshit in it that I'm sure you can safely remove (ex: secondary air pump) and still pass emissions

[CoKid]

Seasons' Greetings, and sorry for the long radio silence! I've been so busy over the last couple weeks I was not able to spend much time on this until yesterday.

To make a longer story full of misadventures short, I did finally take the battery to a male-bonding-center (wife's term for hardware and parts stores). They tested it as "bad", though I'm not 100% trusting the diagnosis, as it was holding a +12V charge for 2-3 days, just sitting.

Anyway, after replacing the batt, I of course got another dozen or so codes. After clearing, driving, clearing a few times, I got it down to just a few, most notably the low beam/"dipped" codes, plus driver's mirror "pivot" faulty. Specific codes are:

9CCF (Drive, pivoting, ,mirror, driver's side, faulty)
9CBA (Communication with LIN operator unit disturbed)
A8AA (Dipped beam, left, faulty)
A8AB (Dipped beam, right, faulty)

(These are Halogen, BTW.) I tried turning them on with the Foxwell, using the FRM Control - they would not come on. I suppose it's possible both lamps went bad over the course of all this, but doesn't seem likely.

Any ideas? Do I still need to do some kind of FRM/closed circuit reset?

[NICKYSIX84]

Hello did you ever get to the bottom of this I'm having similar issues without the no start, I had the FRM flashed/reset but I had a faulty DDE relay (now replaced) I have everything but exterior lights and front windows working. Did you end up replacing the FRM module?

[firen180]

Bump for an update