Roof issues...
- Thread starter Joe4
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Anonymous
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When you say it won't go all the way down, what do you mean exactly ?
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Anonymous
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The roof mechanism is put simply a set of folding arms each side of the roof that are cross braced and covered in fabric, this assembly has attached to it from new the roof motor and pump housed in a plastic bottle ., hydraulic line running around the frame to the rams and an electrical connection to the roof motor from the car.
The roof assembly is mounted into the car on two mounts that bolt with two bolts each side ,into the car behind the drivers and passengers door , in the rear door pillars . These mounts are where the hydraulic rams are attached to the roof mechanism. The roof fabric is extended and folded on this assembly when the roof opens and closes and is also bolted around the rear deck at its rear most point and latched onto the screen at the front most point.
At the front of the fabric section near the windscreen under the internal cowling on the roof is the unlatch mechanism that works solely on electrical power. This is separate from the hydraulic system that raise and lowers the roof .
The roof hydraulic system works with a hydraulic pump being driven by and electric motor attached to it that pumps hydraulic fluid down 4 lines to the hydraulic rams . Each ram mounted on the roof frame on the roof mounting points in the door pillars has two hydraulic pipes going to it , one at the top of the ram and one at the bottom . These hydraulic pipes feed the rams with hydraulic fluid one line at a time as the roof buttons are pressed, if the up button is pressed fluid is pumped down one of the ram pipes to fill the hydraulic ram with fluid, inside the ram is a piston that is forced to the opposite end of the ram , as it's forced away from the fluid entering the ram,it pushes the fluid on the other side of the ram down the other pipe and back to the hydraulic resoviour .
So with two pipes feeding the two rams, the fluid is simply pumped around the system either one way or the other to raise or lower the roof. The rams drive a toothed drive that is attached to the folding roof assembly .
So you press the down button, the roof electrical module sends a signal to drop the door windows, the roof unlatches at the front by electrical motor, and then the roof hydraulic motor kicks in and drives the pump which pushes fluid into the ram that drives the toothed drive which pushes the mechanism to fold away.
The mechanism has sensors mounted on the bolted section of the frame and on the folding section of the frame , these are Hall sensors that work on magnetic detection, when the roof is raised or lowered when the trigger points for fully up or fully down are reached these sensors should talk to each other to tell the roof module to stop the hydraulic operation and complete any other tasks, such as window raising or latch closing .
So if your roof is not working.....
First check the parcel shelf is in the down position , if it's up , the micro switch on the rear bulkhead is telling the roof module it's not safe to lower the roof so it won't . Then check the bypass cable ( red handle in boot ) if this is out even slightly the chance are the roof motor will run but it bypasses drive to the pump and the roof won't move .
Then it could be one of these.....
The roof module could be toast......never had one
The hydraulic pump could be knackered......never had one
The latch motor could be toast........never had one
The roof ( hall sensors ) are not talking to each other .........roof doesn't raise or lower fully........adjust sensors
Something is impeding the roof opening or closing fully ........remove obstruction
Hrdraulic pipe has failed, or resoviour is leaking ......keep having to add hydraulic fluid , roof works slowly ........replace or repair damaged pipe,or resoviour
Most likely though is the roof hydraulic motor which drives the pump. This is mounted on the side of the roof frame passenger side and the removal and repositioning is covered many times in other posts here. But essentially is a poor design and water ends up drowning the motor that drives the pump, remove , revive and relocate.
These motors are very robust and normal within a few minutes a dead motor can be brought back to life in a bath of diesel . Again many posts here on how to revive a dead motor , but you need to make sure you run the motor fully submerged in a diesel bath both ways of at least 5 mins. You should also make sure the bypass valve is free and not seized ( brass ball on side of pump housing ) and that the electrical connections on the base of the pump are nice and clean .
There is nothing too technical about the roof assembly and how it works, but working through a problem in a logical manor can save a lot of guess work . Getting to all the bits can be a challenge but if you search the forum most fixes can be found .
Some members here can help with issues, some will charge you some won't. But with some basic skills most of the issues on these roofs like motor revival and relocation can be done by the owner with a little time and effort .
The roof assembly is mounted into the car on two mounts that bolt with two bolts each side ,into the car behind the drivers and passengers door , in the rear door pillars . These mounts are where the hydraulic rams are attached to the roof mechanism. The roof fabric is extended and folded on this assembly when the roof opens and closes and is also bolted around the rear deck at its rear most point and latched onto the screen at the front most point.
At the front of the fabric section near the windscreen under the internal cowling on the roof is the unlatch mechanism that works solely on electrical power. This is separate from the hydraulic system that raise and lowers the roof .
The roof hydraulic system works with a hydraulic pump being driven by and electric motor attached to it that pumps hydraulic fluid down 4 lines to the hydraulic rams . Each ram mounted on the roof frame on the roof mounting points in the door pillars has two hydraulic pipes going to it , one at the top of the ram and one at the bottom . These hydraulic pipes feed the rams with hydraulic fluid one line at a time as the roof buttons are pressed, if the up button is pressed fluid is pumped down one of the ram pipes to fill the hydraulic ram with fluid, inside the ram is a piston that is forced to the opposite end of the ram , as it's forced away from the fluid entering the ram,it pushes the fluid on the other side of the ram down the other pipe and back to the hydraulic resoviour .
So with two pipes feeding the two rams, the fluid is simply pumped around the system either one way or the other to raise or lower the roof. The rams drive a toothed drive that is attached to the folding roof assembly .
So you press the down button, the roof electrical module sends a signal to drop the door windows, the roof unlatches at the front by electrical motor, and then the roof hydraulic motor kicks in and drives the pump which pushes fluid into the ram that drives the toothed drive which pushes the mechanism to fold away.
The mechanism has sensors mounted on the bolted section of the frame and on the folding section of the frame , these are Hall sensors that work on magnetic detection, when the roof is raised or lowered when the trigger points for fully up or fully down are reached these sensors should talk to each other to tell the roof module to stop the hydraulic operation and complete any other tasks, such as window raising or latch closing .
So if your roof is not working.....
First check the parcel shelf is in the down position , if it's up , the micro switch on the rear bulkhead is telling the roof module it's not safe to lower the roof so it won't . Then check the bypass cable ( red handle in boot ) if this is out even slightly the chance are the roof motor will run but it bypasses drive to the pump and the roof won't move .
Then it could be one of these.....
The roof module could be toast......never had one
The hydraulic pump could be knackered......never had one
The latch motor could be toast........never had one
The roof ( hall sensors ) are not talking to each other .........roof doesn't raise or lower fully........adjust sensors
Something is impeding the roof opening or closing fully ........remove obstruction
Hrdraulic pipe has failed, or resoviour is leaking ......keep having to add hydraulic fluid , roof works slowly ........replace or repair damaged pipe,or resoviour
Most likely though is the roof hydraulic motor which drives the pump. This is mounted on the side of the roof frame passenger side and the removal and repositioning is covered many times in other posts here. But essentially is a poor design and water ends up drowning the motor that drives the pump, remove , revive and relocate.
These motors are very robust and normal within a few minutes a dead motor can be brought back to life in a bath of diesel . Again many posts here on how to revive a dead motor , but you need to make sure you run the motor fully submerged in a diesel bath both ways of at least 5 mins. You should also make sure the bypass valve is free and not seized ( brass ball on side of pump housing ) and that the electrical connections on the base of the pump are nice and clean .
There is nothing too technical about the roof assembly and how it works, but working through a problem in a logical manor can save a lot of guess work . Getting to all the bits can be a challenge but if you search the forum most fixes can be found .
Some members here can help with issues, some will charge you some won't. But with some basic skills most of the issues on these roofs like motor revival and relocation can be done by the owner with a little time and effort .
Dietcokeman said:
I bought the car with the roof not working. So I had never seen the mechanism in action. I revived and relocated the motor and it now works, but not perfectly. The roof unlatches and the motor lifts the roof slightly. Then there is a slight change in the motor noise and it struggles to go any further. If I give it a push, it goes down. When it gets down it stops about 20-25mm short of the latch. If I put it up about quarter of the way then down again a couple of times, it will then go down. Although it won't locate into the latch, but I'm going to remove the latch anyway. I think a change of motor is in order.
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Anonymous
Guest
Sgr74 said:
When you say it unlatches and lift out slightly, is the roof clear of the unlatch process ? If not then you could do with checking the two unlatch hooks at the front of the roof assembly and lub them and put a small amount of grease of the lock bars located in the top of the screen section .
As for the locking down, if the roof is not going all the way down check for any obstructions on the parcel shelf and make sure the rear window section is folding away correctly , as sometime they don't, and this affected the final resting position . As for the actual lock down , early cars have a lock but later cars do not, they stopped around 2006 pre facelift but some facelift cars do have it .
A
Anonymous
Guest
Sgr74 said:
In which case it's either an obstruction, the roof not folding correctly, which it sounds like,as it does eventually go down . But it could be a hall sensor issue . When it doesn't go all the way down does the motor stop running and the windows go back up ?
Dietcokeman said:
Yes the motor stops and they go back up. From inside the boot, with the shelf removed, the roof gets very bunched up. It's difficult to see if it's right or wrong. I am trying to work through all possibilities but every time you try something and think to yourself that should be it fixed now, and it's not, a little part of you dies. Or is that a bit over dramatic?
Sgr74 said:
No its not over dramatic, it is soul destroying but on a postive it makes the feeling when you do eventually fix it all the sweeter!
I guess a process on elimination might be on the cards. Do you live near/know someone with a zed where the motors been reocated to the boot? If so a simple swap over to your car would confirm/eliminate if the motor itself is at fault. At least that would be a start. Have you checked for signs of any fluid loss, I'm just wondering if both hydraulic rams are Ok.
I know one other person close by but his motor is still in the bucket of death. You can get a hold of roof motors easy enough but the hydrolic part not so much. Even speaking to BMW got me nowhere. They want to "book it in for an inspection" =£££££££££££. I will fix it. I don't tend to give in easily. It's just p***ing me off.
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Anonymous
Guest
Sgr74 said:
Ok so when it does this, does the roof eventually sink down to the correct position ( even if it doesn't lock ) ?
Dietcokeman said:
Yes. If I just put it down, the motor pulls it as far as it can then stops and the windows go up. You can physically see the roof rising a bit once the pressure of the motor is off. Once it's been driven for a while the roof kind of settles a bit. As in it goes down a bit more. It does sound like the fabric or hinge problem, I know, but nothing appears out of line.
Quick update on mine... Pulled the motor out and ran it in a bucket of diesel for about 10 mins each way, the motor seemed to gradually increase in speed while submerged so I gave it a good run in both directions making sure it was up to full speed, then while it was off stripped down the pump to see if I could find any obstructions seized parts in the pump...gave it a clean out and a blow through with an air duster and a bit of wd40 on the Bowden valve (not sure if I should have as I'm now thinking I've contaminated my hydraulic oil). Left the pump overnight as it was getting dark when I finished.
I'm guessing I put it back together correctly as when I reinstalled in the z today the pump ran as before although also with the same problem, so I thought I'd try dietcokemans suggestion of swapping the lines over to see if the motor is pushing out enough power in both directions, however once I had swrapped the lines the motor went from working to completely dead :? (Attempted to power from both the car and a separate battery with jumper leads) so was unable to test this theory.
Not sure if I may have spilled some of the hydraulic oil in the motor when swapping over the lines or if the motor has just finally given up the ghost, any suggestions? :lol:
When I attempt to power the motor using an external battery (tested as good) I don't even get sparks from the battery terminals which suggests to me there is a break in the circuit somewhere in the motor, perhaps motor terminals :scratchhead:
I'm guessing I put it back together correctly as when I reinstalled in the z today the pump ran as before although also with the same problem, so I thought I'd try dietcokemans suggestion of swapping the lines over to see if the motor is pushing out enough power in both directions, however once I had swrapped the lines the motor went from working to completely dead :? (Attempted to power from both the car and a separate battery with jumper leads) so was unable to test this theory.
Not sure if I may have spilled some of the hydraulic oil in the motor when swapping over the lines or if the motor has just finally given up the ghost, any suggestions? :lol:
When I attempt to power the motor using an external battery (tested as good) I don't even get sparks from the battery terminals which suggests to me there is a break in the circuit somewhere in the motor, perhaps motor terminals :scratchhead:
A
Anonymous
Guest
Joe4 said:
Sounds like the motor has given up the ghost for some reason , on the bottom of the motor the main shaft sticks out the base a little , this is normally enough to get a drill chuck on . You can then try spinning it with the drill. Sometimes the brushes on the motor can arc onto the armature , you could also try tapping the housing with a hammer as you try to spin it with the drill. If you get it spinning again , I suggest more diesel submerging then wipe off the excess and leave for ten minute to dry, spin a a few times out of the diesel and wrap it in foil and put it in the oven at 100 degrees for 5 mins . Also make sure the base electrical terminal are still intact, I've had at least one where the terminal has broken away after being sat in the water that collects in the original housing. In the case I was able to solder a short wire onto what was left of the terminal and remake a connection. If this doesn't cure the motor you will need to strip it to investigate or get a specialist to do it if it's beyond you . If you search your local area you should find a starter or alternator refurbished that will normally do these motors too, but get a price first , simple brush replacement shouldn't be expensive . Alternatively source a exchange motor. There is a guy on eBay that does them .
A small amount of wd won't harm the hydraulic oil .
A
Anonymous
Guest
Sgr74 said:
It could be a hall sensor slightly out of position . Has the motor been relocated without the roof being removed ? If so it's possible that the sensor has been slightly dislodged and isn't quite in the right position.
This would make sense as when the roof stops and is slightly raised , the hall sensor thinks it's down completely and tells the roof module it's ok the raise the windows. As gravity takes place the weight of the folding roof pushes the rest of the hydraulic fluid back down the lines into the resoviour and the roof sinks to its normal position .
You could try the following, it may work ......
The roof is mounted at the front of the frame by two bolts each side of the rear of the door pillars. If you look just behind each door rear pillar on the inside there are two round plastic trim covers that cover these bolts.with the roof up but unlatched, Remove the trims and loosen ( do not remove ) the bolts . This will give you a small amount of play in the roof mounting , try moving it back or forward , tighten and retry the roof. This is sometimes enough to align the hall sensor . Not always but it's worth a try .
Once you've got the motor working again, Try removing the long triangular plastic trim that runs along behind the bulkhead at the top of the boot carpet and see if it then fully drops. It sounds like there is a possibility that the windscreen is not folding correctly and its catching on the back trim rather than dropping fully into the well.
As Dietcokeman says, slacken off the hinge pivot bolts and let it square itself up too.
As Dietcokeman says, slacken off the hinge pivot bolts and let it square itself up too.
anyone got a decent picture of the motor relocated please
In the process of getting my motor out of its watery grave I detached the pump assembly from the motor thinking it was a good idea but in the process the drive pins etc fell out! I have retrieved the pieces but not sure how it goes back together has anyone got a diagram of the pump assembly please
In the process of getting my motor out of its watery grave I detached the pump assembly from the motor thinking it was a good idea but in the process the drive pins etc fell out! I have retrieved the pieces but not sure how it goes back together has anyone got a diagram of the pump assembly please
