Roof pump issue - fixed!

[jonas123]

Hi all,

My E89 roof has not been working for a while now. I took it to an indie to get it checked over, and the problem appeared to lie in the pump motor. These appear to be in short supply on fleebay and not going cheap! (£399 for the motor, or £750 for the motor pump assembly...)

As a last ditch effort before buying a new motor, I took the old one out and took the cover off. There was no real evidence of flooding / water damage in the pump / battery bay, so I didn't think that was the issue. So it was a bit of a surprise to see this when I took the housing off the motor:



Ok I know, it doesn't look that bad, but that was after cleaning up all the rust and the housing was much worse!

Anyway, I cleaned it all up, reinstalled back on the car and it works!!!! I can not actually believe it was that easy, given that if I took it to a BMW dealership, it would have been a £2500 bill.

 

[RobbiZ4]

I can not actually believe it was that easy, ...

Sometimes the NTC (temperature sensor, can't be seen on your picture, connected to the 2 violet wires) is damaged when water gets inside of the motor. Then the CTM gets an incorrect temperature and stops operating.

 

[jonas123]

I can not actually believe it was that easy, ...

Sometimes the NTC (temperature sensor, can't be seen on your picture, connected to the 2 violet wires) is damaged when water gets inside of the motor. Then the CTM gets an incorrect temperature and stops operating.

I think the rotor had actually rusted onto the stator and seized. The unit itself was getting very hot when i tried to operate, without actually 'operating'.

 

[flybobbie]

But it should never get wet, my 2009 car is bone dry in the boot.
You need to find the leak....was the foam stained.
or did someone swap it out before you bought the car?

 

[jonas123]

But it should never get wet, my 2009 car is bone dry in the boot.
You need to find the leak....was the foam stained.
or did someone swap it out before you bought the car?

I've never seen any water in the boot, but obviously something happened. No sign of excessive water damage, but a few signs around the motor of some staining. I wonder if I had something in the boot itself that leaked or it was a particularly strong storm one night that breached the boot.

 

[mcbutler]

But it should never get wet, my 2009 car is bone dry in the boot.
You need to find the leak....was the foam stained.
or did someone swap it out before you bought the car?

Not necessarily a leak, opening the roof when its wet/damp could introduce enough moisture over time, you might not even have to have neough moisture to see. Warm damp air in the boot will condense on a cold metal pump rotor etc.
Seems a bit weird that the motor is not watertight to me though considering its location and task...