Pinballer66

Hello,

New to the forum but I have tried doing all research prior to posting for help. We did all the basics. Fuses good, removed the module and reflowed/replaced any questionable solder joints. Contacts tested good. Switch has power, the micro switches are good, the unlock motors have power, and the internal microswitches are good when we tested. Both lock motors get 12v when the switch is pressed to open and close. The damn thing still doesnt work haha. Not sure if we are missing something but at this point it has to be something dumb...
The microswitches at the motor behind the pass seat are also good. What else could it be that is keeping it all from working? Any help would be amazing. Next step would be to find the wiring diagram and trace each to see if in the harness but something tells me it hopefully is something more simple.

Thank you!

Shane

systemsc

Read here under Porsche/Cab Top; https://www.systemsc.com/problems.htm

Pinballer66

definitely no water damage or sitting water anywhere.
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systemsc

Did check the oil pressure switch input? Have you directly powered the motor? Could be broken wires along the top frame. And the obvious one, a bad top ECU!

Pinballer66

Did not check the oil pressure switch input. The motors were receiving 12v on meter when switch pressed.

systemsc

Then the top should move or the motors have a bad ground.

Pinballer66

Yes looking like a grounding issue, where do you recommend checking first? along the frame?
Also the oil pressure switch input plays a role in top operation?

systemsc

The motor ground is typically near the motor at the body. Yes, the oil switch is indicated on the ECU end connector male pin.

Goughary

Did you check the ebrake switch. That's a common failure. Top won't work without the ebrake on. When the switch fails, so does your top.

systemsc

The 964 Cab Top ECU only checks for no oil pressure (P). The 993 ECU checks for P and Hd (hand brake).

Pinballer66

Correct me if I am wrong but if the car has to be off to lower the top how could oil pressure play an issue in the top not working?
Also, I checked the engine groundstoday and not seeing any issues unless there is something specific i need to look for... if the engine was not grounded would it technically not start?

Pinballer66

Also I se you are in SoCal, do you have a shop? Could I bring it by for you to look at?

systemsc

Here's the info we discussed;




Note: The 964 only has the P input (not Hd). The P input (ground) is from the oil pressure sender (2 separate outputs - gauge & cab top).

Pinballer66

Huge shout out to Loren from Systems Consulting! He did all he could to help me troubleshoot and narrow down my top issue. We finally were able to meet and he brought one of his good 964 modules and the top we down as the lord intended haha.
Turned out, the previous owner had a shop that swapped the module but they installed a 993 module that never would of worked. Aside from the module he was awesome in trying to help me get it sorted, I am now a Cab Top Expert lol.

0luke1

That convertible top is not their finest hour of engineering. Just remember to use the boot cover every time. Got to love those tenax fasteners.