2004 Z4 Convertible Top Bowden Cable

Bob231

New member
Had to replace the hydro unit due to water damage (no great surprise right?)
Got the top back on the car, and secured it in place with all four mounting bolts. Plugged all the electronics back in. I shimmed the micro switch located in the trunk )because the tray is out )to allow the yellow light go out by the top activation switches and held my breath that all be ok. ..... It was not. Sounds like the hydro unit is operating but the top does not move. I can manually open it about a quarter of the way but that is all. It looks to me like the Bowden Cable is in the in position, it will not pull out at all to allow me to manually retract the top completely any more. I surmise that it is jammed up. Does anyone have any ideas aside from removing the top again to free the cable.
 
Its unlikely that the Bowden cable itself is jammed, but the button on the pump that releases the pressure in the hydraulics might well be. Mine was jammed closed, so pulling the bowden cable had no effect, and it was stuck with gunk that I had to clean off and activate the button a few times to loosen it. If yours is jammed open, the pump will run (that's good news) but the hydraulics wont build up any pressure.

The bad news is - You have to take the motor out again to get at that button :-/
 
If the cable is stuck or the motor has the bypass enabled then you should be able to move the hood easily up and down. If you are struggling to move it then the chances are that the bypass is off.

If the roof isn't moving but the motor is running, then you could have got the hydraulic lines the wrong way round. When I replaced my motor, the hydraulic connections on the new pump were marked differently to the old pump (exactly the wrong way round). There are some threads about this on here. If thats the issue, you can get round it by swapping the electrical connections round in the plug behind the seat. Before you do that though, best if you partly open the roof by hand and then see if the hood retracts when you press the 'Open' button
 
Back
Top Bottom