Convertible Soft Top. up, but no down, Hydraulic motor works

[DINK86]

Hello Ya'll!

I have a convertible top issue that I have not seen mentioned in any forum and google cannot turn up anything for me. This just started happening this evening so I have not been to a repair shop yet.

2006 3.0SI

The top will not go down. When I hold the top down button the windows will lower, the latches will release from the windshield, the hydraulic motor will make a whirring sound (nothing sounds wrong), but there is no movement from the top.

I can pull the red release latch in the trunk and put the top down all the way manually. I can then press the top down button and lock the roof in the down position.

I can then put the red latch back and press the top up button. Windows come down, hydraulic motor makes the whirring sound and the top goes all the way up, latches to the windshield, windows go back up. Perfect.

The top never struggled to go down in the past and has been rock solid for the two months I have owned the car. Top fabric is in like new condition.

What could it be, how do I verify, how do I fix?

 

[Georgio]

Weird one, normally if the motor's shot nothing will move in either direction so it sounds to me like a sensor or microswitch problem. What are you getting lights wise from the top down button when you push and hold and it only unlatches?

 

[GaryT]

Make sure the shelf in the boot is in the down position

 

[sunnchipie]

Same problem as mine. I need to give the roof a shove to get it to lower.
There is very little information about this fault other than it may be lack of oil or a valve?
I'm meeting another forum member on Sat so might have a little more info after that

* Apparently it just needs WD40 on the hinges. Gonna give it a go and will report back....

 

[maxman]

If the car has been sitting in the sun,there could be a little expansion making the roof catches a bit tight.Try opening the roof about half way then spray some 3 in 1 oil into the locking catch on both sides and middle,don't go mad with the oil.
Also a smear of copper grease on the strike plate on the top of the windscreen,were the catches locate
If it refuses to open go for a run to cool the front of the roof or park in shade and see if the roof will open.

 

[jampudding]

I have this problem too. I just push the top a little to help it and it will then go down. When I press to come up all is fine.
I did read in the manual that after a prolonged period of no use the roof my need help to go down.
Shall watch this thread with interest.

 

[DINK86]

Good information everybody, thank you for all the insight.

I had a tick from the engine and swung by a reputable shop to have them check that plus the top. Engine noise is just injectors.

After having an extensive conversation with the mechanic, who has replaced a few tops, he reviewed that it is often water build up due to blocked drain holes. Here is the conclusion have made and will act upon.

1. There is one motor that creates hydraulic pressure. It works, but sounds low on fluid (mechanics opinion).
2. The difference between up and down is not controlled by a valve. The pumps polarity is reversed so it has a forward and reverse.
3. The hydraulic lines have been known to rust and leak between the pump and motors.

With this in mind if the line that takes high pressure to put the top down has a hole, it would not be able to create a high enough pressure to put the top down. However, when the pump runs in reverse to put the top up that line would become a low pressure line and the hole would not matter. However, losing hydraulic fluid means eventually both directions will not work.

My next step is to look up a repair kit that has just the lines and connectors and take a weekend to replace them.

I will let you know how it goes! Any more thoughts are appreciated as it will be a few days until I make the attempt at repairing.

 

[AlpinaRoadsterS]

Maybe you can first phone or write to this man:
http://www.pixelrichter.de/

His number and E-Mail-adress is here:
http://www.pixelrichter.de/impressum.html

He knows everything about the Z4 roof.
I visited him and he replaced my roof pump/motor into the trunk within 1 hour.
In future I will have never ever a problem with it.

Maybe a trip to germany is a option for you. :driving:

(sorry for my bad english)

 

[sunnchipie]

I dont think a trip to Germany is viable!

DINK86

Is there any difference in your roof power when you have the engine on? ie when opening, is there any improvement

Once the engine is running, If Im to give the roof a shove down, once ive brought it up again it will now work - albeit it will struggle.

 

[DINK86]

Sunnchipie,

That is a great question! There is, however, no discernible difference when the engine is running to when it is not.

Another interesting fact is that I cannot push the top into the down position even when holding the "down" button and pushing on the top. I'm a fit person and believe I am pressing with quite a bit of force that should make a difference.

I have now left the battery disconnected for an hour to see if that would make a difference. Issue still exists exactly as it did before.

 

[sunnchipie]

I was hoping youd say something different!
Mine definitely goes down with the engine on, although it struggles. No chance with the engine off.
Ive only just taken the roof bungs out. I think I might try a new battery on Weds so Ill let you know how that goes.
Im not sure about the leak theory you have but its possible. Contradicting myself here but it may be lack of oil.
Where area do you live? I find it interesting how cars in California are experiencing problems. I think. - I thought it would be limited to wet countries!
If it isn't the battery, which now sounds unlikely, you may have to take the roof out to investigate further.
Im gonna have to do the same if mine gets any worse.

Fitted new battery and now its worse! Although slow when it started opening It still worked ok - Now it wont go back. God knows whats wrong with it