Los Angeles
Hi all,
The roof hydraulics on my 2003 E85 Z4 are shot so I manually pull the roof up and down (not really an issue for me). Once I pull it up or down, I use the buttons to activate the latch motor and lock things into place. This works fine most of the time.
The Issue:
When the air temp is below about 73 degrees Fahrenheit (22C), the latching motor audibly and visibly is much slower in both directions. It gets to a point where it's mostly open or closed and then will start (with a loud click/thud) reversing itself back and forth for a second at time (I assume it does this when it doesn't know position?) and the buttons keep blinking red.
Usually if I sit there for a few minutes or pulse the buttons carefully I can get it fully opened or closed and the lights go off. Sometimes I have to restart the car a couple times. The ambient temperature at which it stops working has gone up from about 68 to 73 in the last year. I've had the car for about 4 years but it seems to have only really started 2-3 years ago. Haven't been able to go on many night rides with the top down. It's all very annoying!
Additional Notes:
I would really appreciate any help. Thank you in advance!
The roof hydraulics on my 2003 E85 Z4 are shot so I manually pull the roof up and down (not really an issue for me). Once I pull it up or down, I use the buttons to activate the latch motor and lock things into place. This works fine most of the time.
The Issue:
When the air temp is below about 73 degrees Fahrenheit (22C), the latching motor audibly and visibly is much slower in both directions. It gets to a point where it's mostly open or closed and then will start (with a loud click/thud) reversing itself back and forth for a second at time (I assume it does this when it doesn't know position?) and the buttons keep blinking red.
Usually if I sit there for a few minutes or pulse the buttons carefully I can get it fully opened or closed and the lights go off. Sometimes I have to restart the car a couple times. The ambient temperature at which it stops working has gone up from about 68 to 73 in the last year. I've had the car for about 4 years but it seems to have only really started 2-3 years ago. Haven't been able to go on many night rides with the top down. It's all very annoying!
Additional Notes:
- It works totally fine and quick when it's hot enough outside.
- Gears aren't worn out given that it works the rest of the time and isn't spinning out.
- Position sensors work most of the time, evidently.
- The little spinners in the windshield pockets for the hooks are lubed and spin freely.
- Everything looks fine visually.
- Maybe the grease in the gearbox gets too stiff when it's slightly colder, adding resistance?
- Hall sensors affected by temperature?
- Motor isn't getting 12v when it's cold?
- The battery is fairly new, so it's not that.
- I haven't tested the voltage at the motor yet because I couldn't get the probes at the right angle, but I'll try tonight.
- I guess touchy wires could cause this, but the fact that it still works when hot and for hundreds of up/down cycles makes me think it's not that.
- Not sure what this would even suggest; maybe a relay?
I would really appreciate any help. Thank you in advance!