Congrats! So you pulled out the Allen key bolt again and re-calibrated? Mine is at 6.2k right now with the clamshell open. My gears are all in great shape in the pot 2 as well. Hopefully you can help me understand mine better. Mine clamshell seems to be working properly and the pump runs but nothing opens or closes.
Porsche 911 UK Enthusiasts Online Community Discussion Forum GB
Welcome to the @Porsche911UK website. Register a free account today to become a member! Sign up is quick and easy, then you can view, participate in topics and posts across the site that covers all things Porsche.
Already registered and looking to recovery your account, select 'login in' and then the 'forget your password' option.
C2 cabrio roof issues
- Thread starter YPVS
- Start date
dcapper said:
So what voltage does POT2 show?
I abandoned calibrating mine to 6.2Kohms, as when I did, with the clamshell fully up, the voltage (2.71V) was struggling to rise above the POT 4 value of 2.75v, so the control unit thought it never reached fully up, stopping the roof lowering more than half way, as the POT value remained the same for 3 seconds without reaching it's end point (Value 4 >2.75V)
Instead, with the shell fully up, I took the screw out, the POT off and turned it until it read 2.9V in PIWIS, putting it well above the 2.75v POT2 Value 4. I then refitted and it works.
The only slight issue I have now is POT1 only just gets above it's 3.51V value when the roof is fully down, so sometimes it takes a couple of attempts to raise the flaps, squash the roof fully down and lock the lid. It's getting to 3.51V.
I suspect the POT's get old and the upper and lower ranges on them are not as defined as they were when new.
I've got it spot on now. The control unit on there currently was the replacement one from the US. The roof worked with it, but was struggling for the roof POT to get to the voltage configured for the limit of the roof.
The saved value 6 (fully down) for the roof was 3.51V and my POT was only just getting to 3.51 or 3.53V fully down. Because of this, it sometimes took a couple of attempts to do the final part and bring the side flaps up.
For some reason, I still couldn't run a calibration, but looking through my old screenshots, the original control unit was last calibrated with slightly lower voltage figures, as they were formed using my car's POTS, not one in the US.
Anyway, this control unit only needs a voltage of 3.45v to be fully down, so the roof now goes up and down exactly as designed.
A tip for anyone tackling this issue.
Firstly, check the obvious, damage to framework or clamshell lid brackets.
Secondly, check the side flaps. Try manually moving them away from the end position then try powering with a 9V battery to see if they move. The electrical connector is just to the rear of them. Pop if off and use some wire on the inner two connectors. Don't over do it though, remember the microswitches wont stop the motor at travel end.
Thirdly, if you have PIWIS, under "actual values" look at the saved voltages for the 2 POTS.
POT1 is the roof POT and will have saved ranges from 1-6. 1 is up and locked and 6 is down and locked. They may range from 0.85v or so, up to 3.5V or so. Your current POT voltage reading is above these figures in PIWIS and is live, so will change as the roof is moved.
It should be lower than your POT1 saved value when fully up and must be higher than the saved value 6 when fully down.
POT2 is the clamshell POT on the motor. The manual tells you to calibrate this by setting the resistance to 6.2Kohms then put it back together with the lid up. This didn't work for me, as at 6.2Kohms on my multimeter, the voltage was only 2.51V as shown in PIWIS and the last saved calibration value 4 of the 1-4 values for the clamshell, needed to exceed 2.78V.
I manually adjusted the POT2 until PIWIS read 2.9V on the POT (it can't exceed 3V), then refitted with the shell fully up.
This ^ sorted it.
So "Function inactive - End point not reached" was basically, on lowering the roof (as it worked fine from half way to up and then back down to half way), that the shell opened to max, but the POT never went higher than 2.51V, when the control unit wanted to see it match and exceed the stored calibration value of 2.78V. After 3 seconds of not seeing this value increase, it halts all motor action. After configuring the POT to read 2.9V when the shell was at max sorted it.
I've learnt loads about how these tops work, so hope, as confusing as this might sound, that this makes sense and helps others. :thumb:
I can finally enjoy the rest of the summer, before it goes up on stands over autumn into winter to remove the gearbox for a rebuild, then whilst that's out, replace the brake line that goes over it (as it's starting to week at the joint), plus sort out whatever the oil leak is from the RMS or IMS cover.
Should be totally sorted then.
The saved value 6 (fully down) for the roof was 3.51V and my POT was only just getting to 3.51 or 3.53V fully down. Because of this, it sometimes took a couple of attempts to do the final part and bring the side flaps up.
For some reason, I still couldn't run a calibration, but looking through my old screenshots, the original control unit was last calibrated with slightly lower voltage figures, as they were formed using my car's POTS, not one in the US.
Anyway, this control unit only needs a voltage of 3.45v to be fully down, so the roof now goes up and down exactly as designed.
A tip for anyone tackling this issue.
Firstly, check the obvious, damage to framework or clamshell lid brackets.
Secondly, check the side flaps. Try manually moving them away from the end position then try powering with a 9V battery to see if they move. The electrical connector is just to the rear of them. Pop if off and use some wire on the inner two connectors. Don't over do it though, remember the microswitches wont stop the motor at travel end.
Thirdly, if you have PIWIS, under "actual values" look at the saved voltages for the 2 POTS.
POT1 is the roof POT and will have saved ranges from 1-6. 1 is up and locked and 6 is down and locked. They may range from 0.85v or so, up to 3.5V or so. Your current POT voltage reading is above these figures in PIWIS and is live, so will change as the roof is moved.
It should be lower than your POT1 saved value when fully up and must be higher than the saved value 6 when fully down.
POT2 is the clamshell POT on the motor. The manual tells you to calibrate this by setting the resistance to 6.2Kohms then put it back together with the lid up. This didn't work for me, as at 6.2Kohms on my multimeter, the voltage was only 2.51V as shown in PIWIS and the last saved calibration value 4 of the 1-4 values for the clamshell, needed to exceed 2.78V.
I manually adjusted the POT2 until PIWIS read 2.9V on the POT (it can't exceed 3V), then refitted with the shell fully up.
This ^ sorted it.
So "Function inactive - End point not reached" was basically, on lowering the roof (as it worked fine from half way to up and then back down to half way), that the shell opened to max, but the POT never went higher than 2.51V, when the control unit wanted to see it match and exceed the stored calibration value of 2.78V. After 3 seconds of not seeing this value increase, it halts all motor action. After configuring the POT to read 2.9V when the shell was at max sorted it.
I've learnt loads about how these tops work, so hope, as confusing as this might sound, that this makes sense and helps others. :thumb:
I can finally enjoy the rest of the summer, before it goes up on stands over autumn into winter to remove the gearbox for a rebuild, then whilst that's out, replace the brake line that goes over it (as it's starting to week at the joint), plus sort out whatever the oil leak is from the RMS or IMS cover.
Should be totally sorted then.
As we discussed, my clamshell fully open only read 2.5v. I took out the motor and set it to 2.9v, put it back in, loctite the allen bolt, and it started working. I'm glad I disregarded the 6.2k ohm reading like you said. This should be a sticky.
Your supposed to replace that allen bolt if you've done a manual open. Did you? Maybe it's stretched? I got my overpriced kit for about £50 and all it has is the allen bolt and a couple of other little bits.
I cant remember the calibrated ranges now for fully up and fully down on the clamshell, but PIWIS should tell you and so long as you're exceeding them at each limit, it should be fine. If you cant adjust it to exceed each limit, then the POT must be shot or wiring from POT to Roof ECU damaged/corroded.
I cant remember the calibrated ranges now for fully up and fully down on the clamshell, but PIWIS should tell you and so long as you're exceeding them at each limit, it should be fine. If you cant adjust it to exceed each limit, then the POT must be shot or wiring from POT to Roof ECU damaged/corroded.
Good stuff!
One thing I noticed too, was the stored calibrated values, which the pot needed to reach to exceed the upper and lower limits, were set at different voltages on the 2 different roof ECU's I tried.
I never did find out how you reset or change these stored requirements, so just kept turning my clamshell drive POT with a screwdriver until it showed voltage which exceeded the stored upper limit, then put it all back together. Lower limit wasn't ever an issue, it just was not passing enough voltage to tell the roof ECU that the clamshell was fully up, so it could continue with the roof lowering program.
:thumb:
One thing I noticed too, was the stored calibrated values, which the pot needed to reach to exceed the upper and lower limits, were set at different voltages on the 2 different roof ECU's I tried.
I never did find out how you reset or change these stored requirements, so just kept turning my clamshell drive POT with a screwdriver until it showed voltage which exceeded the stored upper limit, then put it all back together. Lower limit wasn't ever an issue, it just was not passing enough voltage to tell the roof ECU that the clamshell was fully up, so it could continue with the roof lowering program.
:thumb:
dcapper said:
Yes. It was a bit of a fiddle. The blocks at the top for the roof mounts need to come out and it needs twisting in a certain way. It was a while ago and I can't quite remember how now.
I remember lot's of skinned knuckles on sharp aluminium parts though.
Similar threads
- Locked
New Threads
-
-
Wanted 997 Turbo left oil reservoir wanted
- Started by Bubbleheed
- Replies: 0
-
-
-
-
-
De-badging & re-badging Porsche script- Started by Maxie
- Replies: 1
Porsche Model Range
Porsche 911
Porsche 992: 2018-
Porsche 991: 2011-2019
Porsche 997: 2004-2012
Porsche 996: 1997-2005
Porsche 993: 1993-1998
Porsche 964: 1989-1993
Porsche Carrera 3.2: 1983-1989
Porsche Carrera SC: 1977-1983
Porsche 930 Turbo: 1975-1989
Porsche Early 911: 1964-1977
Porsche Hypercars
Porsche 918 Spyder
Porsche Carrera GT
Porsche GT1
Porsche 959
Other Current Porsche Model
Porsche Taycan : (2019-0%)
Porsche Macan : 2013-
Porsche Panamera : 2009-
Porsche Cayman: 2005-
Porsche Cayenne: 2003-
Porsche Boxster: 1997-
Porsche Legacy Models
Porsche 928
Porsche 968
Porsche 944
Porsche 924
Porsche 914
Porsche 912
Porsche 904
Porsche 550
Porsche 356 Speedster
Porsche 356
