Electric roof problem

[vbk1975]

Thanks, vbk1975! I will manually open the roof and inspect the sensor wiring later today. I replaced all four sensors…..initially front two, one of which was very corroded but got same error so replaced the back ones and still same error. If all the wires are correct, I.e. brown to brown, red to red, should I try swapping the wiring round on one side, front and back?

I would look at the hardware menu (link above), then readings are always valid regardless if a fault code is logged or not.

 

[vbk1975]

Sorry……just seen your reply above also…..thank you…..I’ll take a look at the hardware menu when I’m back later

Worth reading to the end of the thread as well, it might help you

 

[tangentman]

Worth reading to the end of the thread as well, it might help you

Hi tbk1975! I followed the instructions and did the following:

• with roof down pulled the 30amp fuse; left it a couple of minutes; put fuse back; ignition off; AN8 and AN9 both 0
• Ignition on; flashing roof icon; AN8 and AN9 both 255
• manually raised roof directly connecting motor; AN8 = 105; AN9 = 255, no errors
• Checked sensors, all wired red to red and brown to brown.
• Lowered roof half way using control unit, no error, AN8 and AN9 both 105
• Lowered roof further using control unit and didn’t quite fully shut, error 1000, both AN8 and AN9 255

Any further suggestions greatly appreciated…..thank you

 

[vbk1975]

Hi tbk1975! I followed the instructions and did the following:

• with roof down pulled the 30amp fuse; left it a couple of minutes; put fuse back; ignition off; AN8 and AN9 both 0
• Ignition on; flashing roof icon; AN8 and AN9 both 255
• manually raised roof directly connecting motor; AN8 = 105; AN9 = 255, no errors
• Checked sensors, all wired red to red and brown to brown.
• Lowered roof half way using control unit, no error, AN8 and AN9 both 105
• Lowered roof further using control unit and didn’t quite fully shut, error 1000, both AN8 and AN9 255

Any further suggestions greatly appreciated…..thank you

i think one of the closed sensors is either defective or there is a wiring issue. I think the system is recognising one closed sensor but not the other one and that is what triggers the error . From memory the closed sensor is the one to the rear of the ram / rear of the vehicle. Worth just checking they are both fully seated and hasn't popped out and/or no damage to the sensor where the cable goes in. Also just double check no stray strands of wiring in the joints touching the other wire. (although this would probably mean a constant fault)

 

[tangentman]

i think one of the closed sensors is either defective or there is a wiring issue. I think the system is recognising one closed sensor but not the other one and that is what triggers the error . From memory the closed sensor is the one to the rear of the ram / rear of the vehicle. Worth just checking they are both fully seated and hasn't popped out and/or no damage to the sensor where the cable goes in. Also just double check no stray strands of wiring in the joints touching the other wire. (although this would probably mean a constant fault)

Thanks so much for swift response again!! I can confirm that all sensors are seated correctly and wiring isolated…..all sensors are brand new from BMW…….do you know if there is a way of testing the sensors? Just to mention, when the roof was open, I tried putting a metal object (socket bits) on each sensor and checked the hardware readings but values didn’t change?

 

[vbk1975]

Thanks so much for swift response again!! I can confirm that all sensors are seated correctly and wiring isolated…..all sensors are brand new from BMW…….do you know if there is a way of testing the sensors? Just to mention, when the roof was open, I tried putting a metal object (socket bits) on each sensor and checked the hardware readings but values didn’t change?

The sensors are two wire Hall effect. So they change the amount of current they flow when not active and active. I think 12-17mA when active. The sensors need a good chunk of steel to get them to trigger. I have 3mm steel bar on my test rig. A M10/12 steel nut works but very hit or miss on anything not pure ferrous metal and a big enough surface area. Because the ECU uses both sides to determine the state, you won’t get one sensor to trigger a warning.

 

[Lambeth Cali]

Hi, the only thing that occurs to me is that there was one extra complication other than red-to-red and brown-to-brown. At one point there were two wires. Could this be the problem? See below pic

The only other thing I wonder about is there a particular bit of the roof that goes close to the sensors to activate the circuit? Is anything looking identical on both sides of the van.

VBK knows a lot more about this than I ever will. I still think I was lucky and fortunate to have people push me on when it didn’t work first time.

How to Replace Roof Sensors

My roof has over the years occasionally said it was up when it was down. I‘ve owned it from 2009 and know the sound it makes when closing so have ignored this. I think last summer this finally became worse. Coincidentally after last summer I decided I wanted to replace the control unit as the...

vwcaliforniaclub.com

 

[tangentman]

The sensors are two wire Hall effect. So they change the amount of current they flow when not active and active. I think 12-17mA when active. The sensors need a good chunk of steel to get them to trigger. I have 3mm steel bar on my test rig. A M10/12 steel nut works but very hit or miss on anything not pure ferrous metal and a big enough surface area. Because the ECU uses both sides to determine the state, you won’t get one sensor to trigger a warning.

Thanks vbk1975…..I wasn’t able to try yesterday due to rain but I have a large crowbar and a bolster that will hopefully give a reading…..will try later.

 

[tangentman]

Hi, the only thing that occurs to me is that there was one extra complication other than red-to-red and brown-to-brown. At one point there were two wires. Could this be the problem? See below pic

The only other thing I wonder about is there a particular bit of the roof that goes close to the sensors to activate the circuit? Is anything looking identical on both sides of the van.

VBK knows a lot more about this than I ever will. I still think I was lucky and fortunate to have people push me on when it didn’t work first time.

View attachment 136302

How to Replace Roof Sensors

My roof has over the years occasionally said it was up when it was down. I‘ve owned it from 2009 and know the sound it makes when closing so have ignored this. I think last summer this finally became worse. Coincidentally after last summer I decided I wanted to replace the control unit as the...

vwcaliforniaclub.com

Hi Lambeth Cali……thank you for your reply….I could only see the red and brown wires on the rear sensors when I swapped them out……I didn’t undo the existing tape holding all the wires together though as had enough length of the red and brown wires when I snipped the old sensor off……are the additional wires you mention under the tape?

 

[vbk1975]

Hi, the only thing that occurs to me is that there was one extra complication other than red-to-red and brown-to-brown. At one point there were two wires. Could this be the problem? See below pic

The only other thing I wonder about is there a particular bit of the roof that goes close to the sensors to activate the circuit? Is anything looking identical on both sides of the van.

VBK knows a lot more about this than I ever will. I still think I was lucky and fortunate to have people push me on when it didn’t work first time.

View attachment 136302

How to Replace Roof Sensors

My roof has over the years occasionally said it was up when it was down. I‘ve owned it from 2009 and know the sound it makes when closing so have ignored this. I think last summer this finally became worse. Coincidentally after last summer I decided I wanted to replace the control unit as the...

vwcaliforniaclub.com

Does this make it a bit clearer. The joint you can see is the common sensor feed that is spliced at the ram.




{EDIT} Just an example but the splice will probably look like this (just an example not the Cali) - it is ultrasonically welded and will be taped or heat shrink.

 

[tangentman]

Does this make it a bit clearer. The joint you can see is the common sensor feed that is spliced at the ram.

View attachment 136326


{EDIT} Just an example but the splice will probably look like this (just an example not the Cali) - it is ultrasonically welded and will be taped or heat shrink.

View attachment 136327

Ah…..thanks so much vbk175……that makes perfect sense……based on this, I guess it is worth me removing the tape to inspect where the common sensor feeds are spliced……I’ll take a look later…..thanks again.

 

[tangentman]

Ah…..thanks so much vbk175……that makes perfect sense……based on this, I guess it is worth me removing the tape to inspect where the common sensor feeds are spliced……I’ll take a look later…..

Hi vbk1975 and Lambeth Cali,

Sorry for delay getting back…..was away over bank holiday and just had a chance to take another look at my van.

I manually raised the roof again and tried putting a lump hammer one side on the rear sensor, a heavy duty bolster on the rear sensor on the other side. When I checked the hardware menu, there was no change to AN8/9 values, no matter where I placed the hammer / bolster!……is there something I am doing wrong? Just to mention, I have had a look at the wiring and everything looks to be ok…….any help really appreciated…..thanks again

 

[vbk1975]

Hi vbk1975 and Lambeth Cali,

Sorry for delay getting back…..was away over bank holiday and just had a chance to take another look at my van.

I manually raised the roof again and tried putting a lump hammer one side on the rear sensor, a heavy duty bolster on the rear sensor on the other side. When I checked the hardware menu, there was no change to AN8/9 values, no matter where I placed the hammer / bolster!……is there something I am doing wrong? Just to mention, I have had a look at the wiring and everything looks to be ok…….any help really appreciated…..thanks again

If you have one of the old sensors (the one looks like it is in best condition), then perhaps swap the rear sensors out one at a time using the old one and do one side at a time. I know this is a pain, but perhaps just use choc wiring terminal blocks to do a quick prove out before committing. If nothing else it will try to eliminate a faulty new sensor.

 

[tangentman]

If you have one of the old sensors (the one looks like it is in best condition), then perhaps swap the rear sensors out one at a time using the old one and do one side at a time. I know this is a pain, but perhaps just use choc wiring terminal blocks to do a quick prove out before committing. If nothing else it will try to eliminate a faulty new sensor.

Hi vbk1975

Thank you for your swift reply and suggestion. Unfortunately, I cut the wires close to the old sensors, so not sure if I will be able to rewire them. However, I have had a small breakthrough in that by using small speaker magnets, I was able to get some readings from the sensors!! With the roof half way down, both AN8 and AN9 show 104 (as expected) if I activate just the rear left sensor, both AN8 and AN9 show 255 and get the error. After resetting, rear left back deactivated and with roof in same position, when I try to activate the rear right sensor only, nothing happens, both AN8 and AN9 values show 104, meaning this must be the one failing!! Regarding the front ones, using the same approach, it appears the front left is not working but this does not cause an error as front right alone seems to be ok. Based on this, I’m going to try swapping front and back right as I know front right works……fingers crossed and will let you know…..thanks again!!

 

[tangentman]

Hi vbk1975

Thank you for your swift reply and suggestion. Unfortunately, I cut the wires close to the old sensors, so not sure if I will be able to rewire them. However, I have had a small breakthrough in that by using small speaker magnets, I was able to get some readings from the sensors!! With the roof half way down, both AN8 and AN9 show 104 (as expected) if I activate just the rear left sensor, both AN8 and AN9 show 255 and get the error. After resetting, rear left back deactivated and with roof in same position, when I try to activate the rear right sensor only, nothing happens, both AN8 and AN9 values show 104, meaning this must be the one failing!! Regarding the front ones, using the same approach, it appears the front left is not working but this does not cause an error as front right alone seems to be ok. Based on this, I’m going to try swapping front and back right as I know front right works……fingers crossed and will let you know…..thanks again!!

Quick update……I managed to wire up one of the old sensors and tested it by switching wires and applying magnet…..sensor gave a reading, so swapped out the faulty one but still the same error occurs I can now get the error when applying the magnet to either side at a time but same error when both rear sensors activated! Could the issue be with the roof ECU or control panel? Any help greatly appreciated as the little hair I have left is rapidly depleting

 

[vbk1975]

Quick update……I managed to wire up one of the old sensors and tested it by switching wires and applying magnet…..sensor gave a reading, so swapped out the faulty one but still the same error occurs I can now get the error when applying the magnet to either side at a time but same error when both rear sensors activated! Could the issue be with the roof ECU or control panel? Any help greatly appreciated as the little hair I have left is rapidly depleting

Can you put the old sensor back on the ram and see if it works with the rams rather than magnets. The sensors have magnets in them, so they are designed to react to the internal of the ram. I am not hopeful but it would be a shame to start chasing ghosts.

It could be the Roof ECU input although I don’t remember anyone with a roof ECU fault, but never say never.

Roof Panel, again it could be, although from memory both the AN signals have reacted to changes.

I am equally frustrated!!