Convertible top mechanism
- Thread starter diksmack
- Start date
Hehe, I have the same problem on my 99, I am working through it right now. I just need more time. But I can tell you a few things:
1. Get a can of spray SILICON (not oil or grease) and carefully lube every joint in the top that you can get to. Hold a paper towel behind to catch the overspray, and wipe off any excess.
2. Check the 4 bolts that secure the motor, exposed inside the cover area. Mine were loose.
3. Do you have what appears to be a little slack in the cover when it is up? In other words, can you lift it up 1/2" - 1" more after it is supposedly open all the way? I can do that with mine. There are 2 gas struts that help lift it. I think they may be weak and not lifting the lid all the way. I bought 2 replacements, just have to find time to replace them.
4. The BMW TIS acknowledges this is a known issue. They recommend the lube, and also indicate that in some cases this may be related to some "tension straps" in the roof itself that have stretched. They recomend replacing them. i have not gone this far yet.
5. Initialize the convertible top's computer:
Initialization of the system is required for the CVM to learn the end limits of the top storage
cover. The CVM counts the pulses from the integrated hall sensor in the cover motor to
determine the cover position.
An initialization run occurs automatically after every eighth operation of the top. This
ensures that the hall sensor counting circuit is not adversely affected by any backlash or
elasticity of the top cover drive mechanism.
The hall sensor counter reading is
stored in a NV RAM, however it is
possible for this data to be incorrect
or out of sync for the following
conditions:
• Power supply interrupted while
top is in operation
• Electrical failures that require
manual closing of the top.
Follow the procedures on this page
or refer to Group 54 in the Repair
Manual of TIS.
1. The top must be placed in the storage compartment
• Motors engaged with the drives.
• Top storage cover closed
2. Ignition key switched OFF.
3. Press and hold the top switch in the lowering direction.
4. Switch the ignition on (KL R).
5. After approximately 10 seconds the top storage cover will start to close and lock.
6. At this point release the the top switch. The initialization procedure will continue running.
The procedure is complete approximately 0.5 seconds after the top storage cover
is closed and locked.
NOTE: The initialization procedure can be interrupted by switching the ignition off.
I have few BMW documents that explain the operation of the top and has the above initialization info, etc. PM me with an EMail address and I send it to you.
1. Get a can of spray SILICON (not oil or grease) and carefully lube every joint in the top that you can get to. Hold a paper towel behind to catch the overspray, and wipe off any excess.
2. Check the 4 bolts that secure the motor, exposed inside the cover area. Mine were loose.
3. Do you have what appears to be a little slack in the cover when it is up? In other words, can you lift it up 1/2" - 1" more after it is supposedly open all the way? I can do that with mine. There are 2 gas struts that help lift it. I think they may be weak and not lifting the lid all the way. I bought 2 replacements, just have to find time to replace them.
4. The BMW TIS acknowledges this is a known issue. They recommend the lube, and also indicate that in some cases this may be related to some "tension straps" in the roof itself that have stretched. They recomend replacing them. i have not gone this far yet.
5. Initialize the convertible top's computer:
Initialization of the system is required for the CVM to learn the end limits of the top storage
cover. The CVM counts the pulses from the integrated hall sensor in the cover motor to
determine the cover position.
An initialization run occurs automatically after every eighth operation of the top. This
ensures that the hall sensor counting circuit is not adversely affected by any backlash or
elasticity of the top cover drive mechanism.
The hall sensor counter reading is
stored in a NV RAM, however it is
possible for this data to be incorrect
or out of sync for the following
conditions:
• Power supply interrupted while
top is in operation
• Electrical failures that require
manual closing of the top.
Follow the procedures on this page
or refer to Group 54 in the Repair
Manual of TIS.
1. The top must be placed in the storage compartment
• Motors engaged with the drives.
• Top storage cover closed
2. Ignition key switched OFF.
3. Press and hold the top switch in the lowering direction.
4. Switch the ignition on (KL R).
5. After approximately 10 seconds the top storage cover will start to close and lock.
6. At this point release the the top switch. The initialization procedure will continue running.
The procedure is complete approximately 0.5 seconds after the top storage cover
is closed and locked.
NOTE: The initialization procedure can be interrupted by switching the ignition off.
I have few BMW documents that explain the operation of the top and has the above initialization info, etc. PM me with an EMail address and I send it to you.