kwr

[KWR73]

Hi - First post, sorry if it's a bit long, but all the forums point to this one when some Boxster expertise is required. 

I have a 2006 987 3.2 S, it has been SORN for a while and whilst SORN i needed to replace the battery.  New battery on with a conditioner now ( lesson learned).   A couple of weeks after the new battery was fitted the clamshell mysteriously opened on its own and I could not close, as soon as I put the keys in the windows opened and the roof would mechanism decided not to work. 

There was some water ingress through the drivers rear drain, but not on the passenger side, so the rear cu seems to have remained dry.

After a number of tries, I finally resorted to removing the pushrods for the clamshell and using a drill to return the gears to limit position.

I've since done a full electrical run through, the centre microswitch is fine, I've replaced the fuses and relays on the off-chance and even have a spare motor, though I am not getting any voltage through the wires on test.

This leads me back to CU - any other ideas? 

Is my best course of action just to take it to an independent and get it on PIWIS to see if the BOXSTER code cleared with the dead battery and have them get the CU out to inspect for corrosion?

Tips on removing the cables from the rear CU would be good too, I didn't want to force and it didn't look intuitive. 

Many thanks

[Menoporsche]

hmm. Welcome  

Yeah that's a poser.  New battery. Under the passenger seat is the rear control unit, I think the alarm control unit is somewhere up on the rear bulkhead now? No water ingress there, running down from the back?

Haven't got a mouse nest after being SORNed?

[Paul P]

Welcome 

first off it does sound like a rear control unit vs water thing.  The foam under the carpet holds a LOT of water and can be soaking underneath with the top feeling dry.  If you have rear parking sensors then the control unit is under the passenger seat as well so double check the operation there.  Rear control unit also does spoiler, brake abs rear lights, boot latch and light (I think) so check all of them.  
 

removing wiring.  Don’t think there is much science except Porsche use suicide plastic that breaks as soon as you look it.  In cold weather a hairdryer on any bit of bendy plastic helps.  
 

where abouts in the country are you. There are a few of us who have access to various flavours of Porsche diagnostic kit that may be able to remove some guessing from rouble shooting.  
 

good luck and keep working on it, between us we will figure it.  

[KWR73]

9 minutes ago, Paul P said:

Welcome 

first off it does sound like a rear control unit vs water thing.  The foam under the carpet holds a LOT of water and can be soaking underneath with the top feeling dry.  If you have rear parking sensors then the control unit is under the passenger seat as well so double check the operation there.  Rear control unit also does spoiler, brake abs rear lights, boot latch and light (I think) so check all of them.  
 

removing wiring.  Don’t think there is much science except Porsche use suicide plastic that breaks as soon as you look it.  In cold weather a hairdryer on any bit of bendy plastic helps.  
 

where abouts in the country are you. There are a few of us who have access to various flavours of Porsche diagnostic kit that may be able to remove some guessing from rouble shooting.  
 

good luck and keep working on it, between us we will figure it.  

Thanks Paul - Where am I, not far from you funnily enough,  Just outside Paddock Wood.  

I really did hope you said that it definitely wasn't the CU, I've seen one the bay, I'll take her over to Project 9 in Marden to check the coding on the off-chance, though it seems it's a new CU that's needed.    

Hopefully the SORN comes off tomorrow with an MOT, a broken roof won't stop me!

@Menoporsche - No mice, a few spiders and a lot of leaves  - 

    

[Paul P]

8 minutes ago, KWR73 said:

Thanks Paul - Where am I, not far from you funnily enough,  Just outside Paddock Wood.  

I really did hope you said that it definitely wasn't the CU, I've seen one the bay, I'll take her over to Project 9 in Marden to check the coding on the off-chance, though it seems it's a new CU that's needed.    

Hopefully the SORN comes off tomorrow with an MOT, a broken roof won't stop me!

@Menoporsche - No mice, a few spiders and a lot of leaves  - 

    

I have the PIWIS diags, happy to plug in and see what it says if you want to come to me - purely an amateur with the kit - but i learn as I go - and I have scanned a few 987's with drowned rear control units.

Leaves and boxsters don't mix - rear drains block, water enters cabin - collects under seats........ don't want t be to harbinger of doom etc. but if its wet fix it before you replace anything - what's the price on the ebay one - 2nd hand ebay often not cheaper than brand new from Porsche 

PM me if you want to plug in and see what it tells us.

[KWR73]

Thanks Paul - I might take you up on that.  I spent last weekend cleaning drains, using the Vax, replacing a rear drip tray and adding those little drain filters.

I found that the funnel top of the off side rear drain had been mashed and the drip tray drain hole was no longer in the funnel top.  I strongly suspect this is why there was a swimming pool under the drivers seat.  

[Paul P]

1 minute ago, KWR73 said:

Thanks Paul - I might take you up on that.  I spent last weekend cleaning drains, using the Vax, replacing a rear drip tray and adding those little drain filters.

I found that the funnel top of the off side rear drain had been mashed and the drip tray drain hole was no longer in the funnel top.  I strongly suspect this is why there was a swimming pool under the drivers seat.  

Cool. Sounds like you are on top of it.

The offers there whenever  

general advice is get a price on parts from Porsche first before hitting eBay. 
 

good luck with it. 

[Menoporsche]

Need to find out where the ACU is at the back and if it was en route between blocked hole and driver seat base. I'm puzzled why the roof isn't working as I didn't think the RCU controlled that.

[Paul P]

Just now, Menoporsche said:

Need to find out where the ACU is at the back and if it was en route between blocked hole and driver seat base. I'm puzzled why the roof isn't working as I didn't think the RCU controlled that.

Rcu def does roof along with spoiler and rear lights.  One of the things that needs to be coded on the rcu is the roof config and I have seen a couple where they got wet and tried to open the roof while it was still latched.  
 

the acu is up under the dashboard somewhere on the 987.  

[KWR73]

I've heard that the RCU can lose coding with a flat battery and was hopeful it would just be a PIWIS job.

Spoiler and rear lights are all working, it's just the roof that is dead right now.

Thanks for tip on Porsche parts will go get a price from them, others have said that Porsche like to see as many cars from the brand on the road as possible.  We'll see if that means a decent price.    

Thanks

    

[Paul P]

The usual amnesia with a very flat battery is things going into transit mode where things like heated seats are forgotten and lights sometimes don’t work.  I guess it’s possible that it the rear control unit could forget it’s in a boxster (same unit in a cayman and a 997) but when I have seen cars with replacement units that needed coding then the roof simply played dead, no window drop on roof latch opening and no response from buttons etc.  
 

in your case it seems the roof tried to open on its own suggesting that it has lost its mind rather than simply forgetting but worth a try to see if a recode can resolve it. 

[KWR73]

Cheers - been on to Porsche - the RCU is £280 + VAT for an obviously new and clean part.  

Best on ebay is comparable - would still need it coded, but, it is a weight off - am thankful its only the RCU there on 987, there was a whole lot more under the seat of the 986   

[ricof]

How bizarre, I had the exact same issue about a year ago (in fact I updated the thread almost one year ago to the day!).

It turned out to be a faulty roof gearbox microswitch and needed a handover reset.

Have a read of my trials and tribulations here: 

 

[KWR73]

7 hours ago, ricof said:

How bizarre, I had the exact same issue about a year ago (in fact I updated the thread almost one year ago to the day!).

It turned out to be a faulty roof gearbox microswitch and needed a handover reset.

Have a read of my trials and tribulations here: 

 

Thank you - any ideas on what the "modification" on the gear microswitch is?  Does anyone if is there a switch in both gears or just in the passenger side close to the RCU?

Still waiting for her to come back from the MOT, so a good Easter job!

 

[ricof]

15 hours ago, KWR73 said:

Thank you - any ideas on what the "modification" on the gear microswitch is?  Does anyone if is there a switch in both gears or just in the passenger side close to the RCU?

Still waiting for her to come back from the MOT, so a good Easter job!

 

The two small levers/gears weren’t engaging with the micro switch properly so they were modified to do so. It was quite a perplexing issue, so much so that one indie admitted defeat. 
 

I believe it’s just in the passenger side only. Good luck with it! It frustrated the hell out of me. Lesson learned - never leave a Box laid up!

[KWR73]

2 minutes ago, ricof said:

The two small levers/gears weren’t engaging with the micro switch properly so they were modified to do so. It was quite a perplexing issue, so much so that one indie admitted defeat. 
 

I believe it’s just in the passenger side only. Good luck with it! It frustrated the hell out of me. Lesson learned - never leave a Box laid up!

Thank you - Totally agree on not leaving them laid up, mine was SORN whilst I moved house and then the pandemic when there were 3 cars on the drive and nowhere to go. 

All the best!