Power cabriolet top issue.

[BlkBird]

My top is always happy to go down. Going up, on the other hand, is another matter. Sometimes it works faultlessly. Sometimes nothing happens. No sound, no motor - nada. Of course try it again the next day and the whole thing works faultlessly

I've loosened the two bolts attaching the cabriolet top to the main motors behind the quarter panels and this lets me manually close the roof. But even with the micro switches on the roof making contact with the window frame the two locking motors refuse to engage.

My local shop replaced one of the microswitches and it seemed to fix the issue. But of course the top stopped working as soon as I got the car home. And then worked fine the next day.

I'm beginning to suspect the control module (passenger foot well) is causing problems. Of course I can't find that part number and I'll bet it is major $$$$.

Has anyone ever converted or re-wired the locking mechanism? I'm thinking it might be best to set the top up so the activation button does nothing more than control the locking motors. Press button - lock/unlock roof electronically - manually raise/lower roof. Anybody done this or have a better fix?

[kidrock]

I'm no expert by any means....but the control module is definitely the last thing I would look at. Personally, I think your problem may either be a bad ground (or grounds) or a dirty, corroded source of power. Find out where your main ground is, and clean it up well. Also, find out which fuse operates the top. Disconnect the battery, clean the fuse and the fuse box contacts and reconnect.

If the problem still exists, it will become a matter of finding the culprit wire. Maybe a wire to the main motor or possible some circuitry inside the control module.

P.S.---many long-time Cabby owners just convert their power tops to manual....because they are generally a PITA.

[glennspiegler]

Mine was the control module.Took out the circuit board and found 3 broken solders. Works well now. Glenn

[Netspeed]

My top cut hung up on the latches and then over-torqued the cables which then popped out of the motors. One side is easy to acquire but the other side is would the opposite way and the dealer wanted $300 for a cable. So....I just removed all the hardware and use the top manually now.

[kidrock]

FWIW, I had an issue with the top getting stuck in the "closed" position. After some wrestling, I got it to open and found out the guide pin on the driver's side was loose and wobbly. I tightened it up and made some slight adjustments on the driver's side adjustment nut and now it works great again.

But I still believe that the PO has an electrical bug somewhere....hopefully, just a ground or something needing a little cleaning or attention.

Any progress on this?

[BlkBird]

Folks,

Problem solved!
- Tested the two switches that contact the window frame when the roof closes using a multimeter. Switches appeared to be working fine.
- Pulled out the two locking motors and applied 12 to the power points - motors both worked fine and, might I add, very quickly. Don't want to apply power to them for too long as they will likely break the locking mechanism.
- Measured the resistance of the two micro-switches that stop the locking motors. And found a discrepancy.
--- At full open, both micro-switches showed an open circuit.
--- In between full open and full close, both micro-switches showed a closed circuit.
--- At full lock, one micro-switch showed an open circuit. The other continued to indicate a closed circuit.
--- Removed the four bolts holding the lock mechanism together. Inside is a worm gear, a brass gear and a small micro-switch. The micro-switch has a small arm with a plastic roller at one end. The roller makes contact with a small plastic cam that is attached to the brass gear with a small bolt.

By manually turning the locking arm, I could watch the brass gear rotate with the attached plastic cam. On one of the units (passenger side) at both full open and full closed, the plastic cam pushes against the roller on the micro-switch, bending the arm and depressing a small button on the micro-switch. Breaks the circuit and the multimeter shows open.

But on the other unit (drivers side) the cam would make contact at full open with the arm, bend the arm and open the circuit. On full lock, the cam would just barely touch the roller and the arm would not bend enough to depress the small button, and the circuit would stay closed.

Enter the Pelican Forum. After searching the board I found someone else's research and determined that the correctly functioning unit was the passenger side. In otherwords, the cam should break the circuit at either full lock or full open. If the circuit is not broken then the computer for the top does not know what the status of the locks is, and it will not even try to open or close the roof. Guess that saves the roof from being pulled apart.

Remember that the small plastic cam is attached to the brass gear with a small bolt. Loosened up the small bolt and nudged the cam slightly to one side using a small screwdriver as a pry. Rotated the locking arm manually and sure enough, the cam now actuated the arm and thence the small button at both open and lock, breaking the circuit. Tightened up the small retaining bolt GENTLY. Remember this is a brass gear and I didn't fancy stripping any threads.

Reassembly was straightforward. Put the roof in the full up position and pressed the open/close button. Sure enough both motors turned the locking mechanism and snugged the roof right down. Reversing the button and both locking motors open the mechanism. After that it was just a matter of tightening the bolts that hold the up/down gear to the roof skeleton. A few more tests and everything was working perfectly.

Cost of replacement micro-switches - nada.
Cost of replacement computer brain - nada.
Replacement motors - yep, nada.

Just a matter of taking your time and measuring everything twice. Or four or five times for those of us who want to be really, really sure. So that was fun. Now on to the next car project!

[kidrock]

That is great news. I have not yet had to delve quite as deep as you have to find past issues I've had with my top.

Question: where are the microswitches that stop the locking motors found?

I have had an intermittant problem with the dash light staying on, indicating an "open top" issue. Maybe I can use your hard work to locate my personal issue....thanks for the write-up.

[BlkBird]

Kidrock,

The locking motors are under the roof liner. The liner itself is a piece of leather over a hard plastic shell that snaps into place using plastic expanders. Once you remove the two handles on either side, the liner pretty much just unsnaps.

Each motor is held in by four bolts. Undo those and the four-wire harness, and the motors should each come right out. Then you can open the locking mechanism by removing an additional four much smaller bolts. Pry it apart with a flat head screwdriver and the mechanism is revealed.

Sorry no photos, I was pretty excited when I realized I'd found the root cause of my problem.