Vanne roof, bit of a less fun post..

I wonder if the wires in the harness have cracked insulation and that’s causing the shorting to ground
 
I’d say so, I’ve got another issue… the windows don’t want to initialize.. well the front 2 do, but the rear ones don’t. And since I’ve re initialized the front 2, they no longer drop a bit when you open the door..

Also the rear boot is now working with the bmw logo..

The errors are gone, however the a68C, returns when I close the boot.

I am also getting a low voltage warning from the battery, which could be the issue with the windows..

So calling it a day today, I gotta go to work in a few hours to Orlando, time at the hotel do do some more reading there..

But I think the rear windows is what is causing the system to not respond…

First a new battery… then hopefully someone has some ideas to re-initialized the windows.. btw, all the window buttons work as they should, and the big one does all of em at the same time.

(I did note before ri re-initialized the front windows, that all windows reported live data closed (when closed) accept the front right, that reported intermediate, (when it was closed) which is why i tried to rye-initialize them.

I can re-initialize the front 2 with Pro-tools, but errors out when I try all of them. (Doesn’t even attempt to do it)

Again, any hints, or help would be hugely appreciated :)
 
No, I don't think that will work?, I can close them manually, no problem, but they are supposed to initialize for the roof to work as the roof controls the rear windows (and front) when it operates. If it (it being the CTM) can’t control the windows, then the roof won’t operate, at least that’s what my logic tells me.

I am sure someone else prob knows how it actually works.
 
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Have you tried lowering each window individually and holding the button down for a few seconds and then raising them and holding the button again for a few seconds, do it a couple of times and then see if the fronts drop when you open the door.
 
Ill give it a go when i get home from Orlando in a few days.. however, i do think ive tried that, its also possible that its acting up due to a flat/low voltage battery.. which is what iam hoping.. will see, in the mean time, ill need to confirm that that CTM controls the windows and why it doesnt wanna do that.

also , when i carefully removed the front roof liner, there is evidence near the front 2 locks of tampering.. again a shame..

really hoping i haven't bitten off more than I can chew with this car.
 
Thanks man, appreciate the pep talk.. ill contimue my reading and then hopefully have a plan when i get home in a few days. Happy to be away from the car atm, it kinda stomped me that the CTM wasnt throwing any errors, after clearing them, and then decided to throw the same A68C error once i manually close the boot. (no read lights flashing on the buttons, untill i close the boot)

I look at the Pro-tools live data, and it shows me that the boot microswitches are closed (which they should be) and that the boot hall sensor is packed (which it also should be) i might need to look at what pins control the hall sensors in the boot.

either that or ill need to see why the rear windows wont initialize ... hmm..
 
Don’t know if you’ve read this but it may be helpful
 
I did read that, and i think i need to tackle the windows issue first.. either that or the rear boot isnt locked even though the switches say it is.

also came across this

Troubleshooting Failed Initializations
    • Check battery voltage: Low system voltage prevents the JBE from completing module routines. Ensure your battery is fully charged or jumped. [1]
    • Inspect the hardtop/convertible top status: On the E89 Z4, the JBE shares signals with the Convertible Top Module (CTM). If the roof is unlatched or stuck in a microswitch fault state, windows may lock out.
    So yeah ill have a look once i fix the battery, thats prob step one. or not.. lol who knows.. but thats prob a good point to start first at. :D
Chippie, thanks for the link mate, but i cant access that pdf for some reason, but i did rear the webby version of it, before he made a pdf of it.

also just spit balling some ideas ill try when i get home..

Sometimes the top is physically closed but hasn't compressed the microswitches fully. [1, 2]
  • Ensure the luggage compartment/trunk partition is firmly locked into its lower position.
  • Insert your physical key into the driver's door lock cylinder.
  • Turn the key to the Lock position (left) and hold it continuously for 20 to 30 seconds. This signals the CTM to run an emergency closure cycle and can force the roof hooks to fully clamp shut.
  • Turn the key to the Unlock position (right) and hold it for 20 seconds to see if the windows drop. [1, 2]

(which is one of the reasons that the windows are locked out)

e89 jbe can't initialize windows



To fix a BMW E89 window initialization failure controlled by the Junction Box Electronics (JBE/JBBF), turn the ignition on without starting the engine. Press and hold the window switch down until fully open, hold for 15–20 seconds, then pull the switch up until fully closed and hold for another 15–20 seconds. [1, 2]

Manual Reset Steps
  • Turn ignition on: Press the start button without putting your foot on the brake.
  • Lower the glass: Press and hold the window switch down until the window is all the way open.
  • Hold at bottom: Keep holding the switch down for 15 to 20 seconds to reset the limit and pinch protection.
  • Raise the glass: Pull the switch up to the second click position until the window is fully closed.
  • Hold at top: Keep holding the switch up for 15 to 20 seconds. [1, 2, 3, 4]

Troubleshooting Failed Initializations
  • Check battery voltage: Low system voltage prevents the JBE from completing module routines. Ensure your battery is fully charged or jumped. [1]
  • Inspect the hardtop/convertible top status: On the E89 Z4, the JBE shares signals with the Convertible Top Module (CTM). If the roof is unlatched or stuck in a microswitch fault state, windows may lock out. [1, 2]
  • Use a diagnostic tool: If manual holding fails, use a BMW-specific tool like ProTool or BimmerGeobs/Standard Tools to clear JBE fault codes and run the active "initialize windows" service function.
all windows and yes warning lights on the roof button


The warning lights on your roof button mean your window initialization failure is a symptom of a convertible top fault, not a broken window system. [1, 2]
On the BMW E89, the Junction Box Electronics (JBE) and the Convertible Top Module (CTM) communicate directly. As a safety feature, if the car cannot verify that the hardtop is 100% closed, locked, and secure, the CTM instructs the JBE to lock out and disable window functions to prevent the roof mechanisms from striking and breaking the glass. [1, 2, 3]
You will not be able to initialize or properly operate the windows until the roof fault is addressed. [1, 2]

Immediate Steps to Resolve the Lockout

1. Try a Manual Roof Mechanical Reset
Sometimes the top is physically closed but hasn't compressed the microswitches fully. [1, 2]
  • Ensure the luggage compartment/trunk partition is firmly locked into its lower position.
  • Insert your physical key into the driver's door lock cylinder.
  • Turn the key to the Lock position (left) and hold it continuously for 20 to 30 seconds. This signals the CTM to run an emergency closure cycle and can force the roof hooks to fully clamp shut.
  • Turn the key to the Unlock position (right) and hold it for 20 seconds to see if the windows drop. [1, 2]

2. Identify the Flashing Light Pattern
The light on the convertible top button tells you where the system is stuck:
  • Flashing Red: The roof movement is unlatched or interrupted (often a microswitch or wiring issue).

------
A flashing red roof button when the hardtop is physically closed means the Convertible Top Module (CTM) did not receive a final confirmation signal from the microswitches to prove the roof is fully locked shut. Because the CTM thinks the roof cycle is still running or incomplete, it is actively locking out the Junction Box Electronics (JBE), making it impossible to initialize or roll your windows up or down. [1, 2, 3]
You must satisfy the CTM's locking sequence before the window system will unlock.


and

Step-by-Step Triage for a Closed Roof with Flashing Red Light

1. Perform a Hard Battery Reset
The CTM can easily get caught in a software loop if a sensor signal drops momentarily.
  • Turn the car completely off.
  • Disconnect the negative battery cable in the trunk.
  • Wait 15 to 20 minutes to completely drain the modules' capacitor memory.
  • Reconnect the cable. Start the car, and immediately check if the flashing red light turns off or if you can now pull the windows up. [1]

2. Clear Obstructions and Cycle the Trunk Partition
The E89 is incredibly sensitive to the luggage compartment tray position. [1]
  • Open the trunk manually if needed.
  • Unhook and reset the trunk partition multiple times to ensure it snaps cleanly into its lower position.
  • Even though a bad partition switch usually triggers an amber or solid red light, a faulty or loose sensor sequence can cause permanent cycle failure, resulting in a flashing red error. [1, 2, 3]

3. Manually Compress the Cowl Hooks (If Slightly Unlatched)
If the hydraulic pump shut off milliseconds before the roof fully clenched into the front windshield cowl, the microswitch will register as open. [1, 2]
  • Sit in the car with the ignition on.
  • Press and firmly hold the roof "Close" switch down for up to 60 seconds. Listen closely for any motor hum or mechanical clicking near the top of the windshield.
  • If you have a helper, have them gently push down on the outer front edge of the roof shell from the outside while you hold the button to help the latches grab.


Ill run through these when i get home
 
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okay new batt, front windows initialize perfectly, and the slight drop also works. so that was def batt related..

the rear windows dont go full up if i just click it once, they drop by like 2 inches at a time, unless i hold it down or up. weird.

also the sunroof module had a a690 code in it.. no idea why.. .. ill much around with it some more tomorrow. still has the flashing red light on the button.
 
okay new batt, front windows initialize perfectly, and the slight drop also works. so that was def batt related..

the rear windows dont go full up if i just click it once, they drop by like 2 inches at a time, unless i hold it down or up. weird.

also the sunroof module had a a690 code in it.. no idea why.. .. ill much around with it some more tomorrow. still has the flashing red light on the button.
Getting there!
 
And then...

he-got-this-borat.gif


OMG!! What an exercise in logic and old skool resistors.. Lol.. Wth..
I was nearly contemplating turning it into a manual power assisted roof.. Lol..
Finally cracked it.. Turns out when you try and fool the CTM, it doesn't appreciate you borrowing resistance from the other switches.

IMG_20260821_202101.jpg
So yep.. 3 errors , which means now comes the fun part trying to repair the wires from both micro switches and the single hall sensor in the roof..

IMG_20260821_202052.jpg
I'll explain here in more details for others if they come across a similar problem. The CTM is all about resistance.. The switches (the hall sensors are also switches) are either open or closed.. And the resistance along the circuit changes depending if its open or closed..

But yeah, I'll add all my notes when I fiinsh my 12 JD& Cokes..
 

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And then...

View attachment 299443


OMG!! What an exercise in logic and old skool resistors.. Lol.. Wth..
I was nearly contemplating turning it into a manual power assisted roof.. Lol..
Finally cracked it.. Turns out when you try and fool the CTM, it doesn't appreciate you borrowing resistance from the other switches.

View attachment 299444
So yep.. 3 errors , which means now comes the fun part trying to repair the wires from both micro switches and the single hall sensor in the roof..

View attachment 299447
I'll explain here in more details for others if they come across a similar problem. The CTM is all about resistance.. The switches (the hall sensors are also switches) are either open or closed.. And the resistance along the circuit changes depending if its open or closed..

But yeah, I'll add all my notes when I fiinsh my 12 JD& Cokes..
Scotch loks never fill me with joy..WCPGW
 
okay... and then we look a bit further...

roof shell 2... right side microswitch GONE.. just not there.. Left side microswitch is there, but sheared wires to the switch.. also sheared wires to the right switch evident... I have no idea if the left switch works.. ill deal with that tomorrow.. I hope the switch works.. Ill see if i can wire both poles to that single switch.. might be possible.. will need to have a look, and or order a new switch..


IMG_1934.jpeg
(Missing right microswitch)

Roof shell 2 hall sensor..

Hall sensor is there, no idea if it works, nor can I clearly see what it lines up with then it’s “packed” or closed?

IMG_1932.jpeg


IMG_1931.jpeg IMG_1930.jpeg

Is that the correct position for the hall sensor? This is the only 2 wires that are connected.. so the break would be in the loom somewhere, I’ll track that down no worries, but am a bit worried about what sits against the hall sensor when it’s closed?

More stuff for another day.. lol..I’ll chalk this one down as a good day. :D
 

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