Chalkie

Wow. I-bus drops to zero volts when key is turned to on (position 2). That is really interesting, as ibus is active-low - usually 12V, then pulled low by devices as required. This means either the main brain has something fruity going on, or some device that’s not on in accessory position is coming on when key is on, and dragging the ibus down to ground 0V. I’ll disconnect ibus line from the brain and see if it stays high on the brain.

I suspect the issue is iBus-related. Will confirm.

Update: the steering wheel radio controls don’t do anything when this issue occurs. After 5 or 10 seconds, the display goes blank. Will check ignition barrel switches as recommended above.

Ok cheers will check that and update.

If key is in accessory position (1), everything works fine. If key is in ignition position (2), the radio controls (in fact all the controls on the widescreen monitor) stop working, and the display stops updating. If I switch the key back to 1, everything works fine again. Here’s what I’ve tried so far: - substituting the boardmonitor for a presumed good one - disconnecting the Nav (Mk 4) to allow the video module to drive the display - swearing at it Any ideas? Video module? Main computer? Wiring? God hates me? Cheers!

NB. Is X10117 on E38/39. No idea on E46. Different LKM?

Wow this is an old topic. Do Euro Homelinks actually exist in that old 3-button E38/E39 unit? Do combo US & Euro units exist also? I suspect rear-view mirror from later model is only way to get that. Cheers, Nathan.

You're correct, if the Nav is present: it will drive the monitor and the menus. However, if it's not present, then system will 'fall back' to having the video/TV module to drive the monitor & you'll see the older style menus displayed. You'll also get day/night mode if you are just using video/TV module. I wish Nav had that feature.

I've answered my own question: yes, it should just work. And now it does. Although I had removed Nav, then left car off overnight, I still had black/blank image on my monitor. I then dropped my kids off at school, so car was off and doors closed for hmmm maybe 10 mins. When I got back in, it was working. Am pretty sure this is same behaviour I saw previously. Couple of possible logical answers in there as to how it registers/deregisters units I guess.

My E38 Mk 4 Nav and widescreen video module work great. 16:9 display. However, when I remove the Nav (doing some troubleshooting) then I only get a black screen on the monitor. Hmmm...I thought that should just work. Any wiring changes required?

Anybody got any good clear photos of either CiC or NBT maps for NZ? Also, does TMC work in NZ for CiC or NBT BMWs? Thanks!

Sussed! Nope, and that's the issue. Nav radio module old gen does not have TEL ON on pin 10. It has GAL on pin 10. GAL is active low, so by default is pulled high to 12V (even with key off). Hence my battery flat issue, since I'd connected old gen pin 10 to new gen pin 11. Also, TEL ON does not go up/down with a call (unlike Tel Mute). As others have described, it's 12V if one or both of the following are true: R terminal is on, or call in progress. Only goes off when no call in progress and key off. Works like a charm. Leaves one unanswered question - how come none of the BMW new gen radio retrofit docs mention this? You can't get TEL ON from an old gen nav radio module connector, so you need to run a wire to elsewhere.

Hmmm, all the WDS diagrams for 1st generation E38 show speedo signal on the old round pins pin #10.

So what I don't get is this: if old gen pin 10 is GAL, and new gen pin 11 is Tel On, then I would expect to see some of the BMW retro-fit docs for new gen radios mention this, and where on earth would an old-new radio adapter cable get Tel On from? Very interesting stuff, really appreciate all the help on this forum, and can't wait to completely get to the bottom of this. Cheers!

No handset, car has never had an eject box. I'm not considering connecting TAA to pin 11 of the loom's radio connector, I am wondering if that's what the signal present on the loom already is. It remains high even after I disconnect the BM54 and disconnect the ULF. Weird huh? Edit: @Neal, yeah I will direct from ULF to BM54 and see what that line does. Edit: Right, I think I get it. PIN 11 on New Gen flat pins is not the same as PIN 10 on Old Gen round pins, for E38/E39 with LCD. On old gen, that was GAL (speed). BMW's documents for New Gen state that GAL is now via I Bus. In summary: Pin 10 on old gen is explicitly listed as GAL/Speed Signal in BMW official docs. Pin 11 on new gen is explicitly listed as Tel On in BMW official docs. I must disconnect Speed Signal from my radio, and ensure Tel On from ULF connects to radio pin 11. Thanks guys, much appreciated, I will make the change tomorrow-isn and report findings.