Troubleshooting 1990 944S2 Cabriolet Top Operation

[RichardBartlett]

Trouble Shooting 1990 944S2 Cabriolet Top Operation

Purpose of this article is to give you some steps to troubleshoot a cabriolet top not going up or down. You will need two pdf files:
Parts Catalogue from Porsche:
http://www.porsche.com/all/media/pdf/originalparts/en/E_944_91_KATALOG.pdf
Pages 309, 314, 364, 371, and 284.
Sealing your 944S2 Cabriolet:
http://www.968forums.com/Miscfileupload/968CabTop.pdf
Pages 9-14 (This Service Information Technik Guide actually discusses all things dealing with the 944S2 top, even though it is on the 968 Site.)
Assume:
Top is in the down position
Windows are in the up position
Begin troubleshooting:
1. Ignition Key in ignition, turned to position 1, radio turns on, windows operate but the dash instruments are not functioning.
2. Doors closed
3. Press the top tip switch (944 613 123 00) to raise the top:
Q1. Do the windows open about 2”?
A. Yes-- this indicates the electrical systems are good, the relays are working, go to Q2.
B. No--- electrical problem. Fuse, relay for window lowering (944 615 119 00), wiring.

Q2. Do the motors make noise? (Motors are located above rear seats)
A. Yes---This indicates the electrical is good and the motors are probably good. Go to Q3
B. No----Electrical issue, fuse, wiring to motors, bad motors, repair as necessary.

Q3. Does the Top move?
A. Yes—This is a good sign, release the top up button. Go to Q4.
B. No----Connection between the motors, which are working, and the Transmission (911 561 045 68 and/or 911 561 046 68) could be the problem. Cable from motors to Transmission either short in length, broken, or top is in “Manual Mode”. Repair
Q4. Press the top up button--Do both sides of the top raise equally?
A. Yes--- Continue holding the top up button, release if you hear any strange noise. Carefully continue raising the top 3” at a time, checking the top for mechanical problems. Go to Q5.
B. No---- STOP, release the top up button!! Only one motor and/or Transmission is working, any further movement will cause expensive harm! You will need to synchronize the two transmissions.
Q5. Does the top stop as it contacts the top of the windshield frame?
A. Yes---The top is operating normally, pull down on the Finger Plate in the middle of the top to seat the top to the window, latch the two latches to secure the top.
B. No----You will need to adjust the position of the microswitch plate located on the Passenger’s side transmission. The upper switch controls the travel of the top forward. It is possible you will need to adjust the convertible top at the Joint Fork (941 561 599 10) on each side. This controls the forward position of the top.
After repairing/adjusting various parts of the top mechanism and going through the check list answering Yes to all questions, carefully operate the top up and down, observing both sides of the top, to be sure they are synchronized and are freely operating.