roof light while driving and roof stuggling to close

gillianb · Post by **gillianb** » Wed Feb 20, 2019 10:45 pm

Hi, the roof light has come on on the dash a couple of times while driving. At the weekend I tested the roof and it dropped with no problem but struggled when closing (but did) - does this sound like a hydraulic fluid is low? Perhaps light going on due to low fluid sensor activating when driving? Would be delighted to hear if anyone has had a similar problem! thanks!

tintoverano · Post by **tintoverano** » Wed Feb 20, 2019 11:02 pm

I had similar symptoms when battery was not charged enough, it was also quite cold winter days - I just bought the car and had to try opening/closing the hood, then for several days I had not locked alert, till I decided to charge the battery, also the car is in the garage since

road warrior · Post by **road warrior** » Wed Feb 20, 2019 11:12 pm

the light will stay on if its not fully into locked position i think

gillianb · Post by **gillianb** » Wed Feb 20, 2019 11:17 pm

the light is only coming on once a week or less, so I believe it is fully closed...

Smartbear · Post by **Smartbear** » Wed Feb 20, 2019 11:17 pm

gillianb wrote: ↑Wed Feb 20, 2019 10:45 pm Hi, the roof light has come on on the dash a couple of times while driving. At the weekend I tested the roof and it dropped with no problem but struggled when closing (but did) - does this sound like a hydraulic fluid is low? Perhaps light going on due to low fluid sensor activating when driving? Would be delighted to hear if anyone has had a similar problem! thanks!

Hi, the light will come on if you try & activate the roof while going around a bend or over particularly bumpy ground.
Best done on smooth level & straight ground

Rob

gillianb · Post by **gillianb** » Wed Feb 20, 2019 11:19 pm

that is interesting thanks- it has been very cold off and on lately adn would explain the the difficulties in closing the roof...I wonder if the light coming on once or twice was unrelated...as it really was sporadically while driving along....will check battery

gillianb · Post by **gillianb** » Wed Feb 20, 2019 11:22 pm

Smartbear wrote: ↑Wed Feb 20, 2019 11:17 pm
gillianb wrote: ↑Wed Feb 20, 2019 10:45 pm Hi, the roof light has come on on the dash a couple of times while driving. At the weekend I tested the roof and it dropped with no problem but struggled when closing (but did) - does this sound like a hydraulic fluid is low? Perhaps light going on due to low fluid sensor activating when driving? Would be delighted to hear if anyone has had a similar problem! thanks!
Hi, the light will come on if you try & activate the roof while going around a bend or over particularly bumpy ground.
Best done on smooth level & straight ground
Rob

I perhaps should have been clearer - I was just driving along without trying to activate the roof - which is why I wondered if the fluid was low then if might activate a sensor? The only time the roof has been down since the end of summer was to bring a christmas tree home

who ever said a z4 was not a practical car???

Deepseaskateboard · Post by **Deepseaskateboard** » Wed Feb 27, 2019 11:30 pm

gillianb wrote: ↑Wed Feb 20, 2019 10:45 pm Hi, the roof light has come on on the dash a couple of times while driving. At the weekend I tested the roof and it dropped with no problem but struggled when closing (but did) - does this sound like a hydraulic fluid is low? Perhaps light going on due to low fluid sensor activating when driving? Would be delighted to hear if anyone has had a similar problem! thanks!

Its probably a microswitch.

Don’t mess with hydraulic fluid, as the roof system is very expensive.

If you can figure out at which part its failing on closure, you can use the guides on here to pin point the corresponding switch or sensor.

My guess is a microswitch has failed, as its a common fault.

Replacment at bmw is about £190

tintoverano · Post by **tintoverano** » Thu Feb 28, 2019 8:00 am

I had this couple of month ago (for me it was battery issue, see above) and researched it

here's the thread viewtopic.php?f=45&t=75740&sid=66ddfbbb ... 5&start=15

for others it was a microswitch as Deepseaskateboard says

flybobbie · Post by **flybobbie** » Thu Feb 28, 2019 9:40 am

The switch that has often been replaced was on the rear right boot ram, my problem was a intermittent connector down there.
Seems it has no locking mechanism. Once fully pushed home and cable tied, no more problem.
The switch tells the system the boot is fully open. My problem was as lid stowed in boot, the system would freeze.
I wonder if a break in any switch or cable, as they seem to have a continuity resistor in them throws up a roof light warning.
viewtopic.php?f=46&t=106166

I think BMW know it's a known problem as the replacement microswitch is a one part cable and not two parts as they originally came out of the factory.

Smartbear · Post by **Smartbear** » Thu Feb 28, 2019 10:44 am

flybobbie wrote: ↑Thu Feb 28, 2019 9:40 am The switch that has often been replaced was on the rear right boot ram, my problem was a intermittent connector down there.
Seems it has no locking mechanism. Once fully pushed home and cable tied, no more problem.
The switch tells the system the boot is fully open. My problem was as lid stowed in boot, the system would freeze.
I wonder if a break in any switch or cable, as they seem to have a continuity resistor in them throws up a roof light warning.
viewtopic.php?f=46&t=106166

I think BMW know it's a known problem as the replacement microswitch is a one part cable and not two parts as they originally came out of the factory.

I wonder if later e89’s came with the one part cable from new?

Rob

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