Had for a while the 5th Bow hitting the storage lid - now a known issue as the bungees (Nissan tech doc Classification BT19-012, Reference NTB19-061 issued Aug 1st 2019). Others in the forum have identified this as the document to use to fix it - and it is a good one too. Sadly however it's a fraction too big to attach here.
Asked a Nissan UK dealer for the requisite part (971F6-1ET2A), to be quoted £850!
Walked out in disgust, went to another dealer in case there was a funny being played - to be quoted again £850 (iro $1200).
Walked out in disgust again.
Part number found on eBay, sold by
https://www.ebay.com/usr/courtesy-nissan who charged $150.
I did ask the dealer what the hell Nissan UK are playing at - needless to say he hid behind 'company policy of no idea'. But IMHO it seems because of Covid they haven't sold anything like their usual quota of new cars, someone somewhere has decided to screw the owners of existing ones to bolster their income stream via parts pricing instead.
During the while this 5th Bow issue existed, another appeared - that of the roof locking shut and not responding at all to the button.
The Roof (RF) section of the [2011] 370 Service Manual - when you work out their workflow logic, indicated a fault with the 5th Bow locking mechanism can totally disable the roof mechanism - my problem.
But what exactly did that mean?
Had to resort to checking the computer error codes for this..
Google revealed an iCarSoft OBD11 device - one of very few of the many diagnostic units available which is suitable for use across all processors in this car.
That allowed a Roof diagnostic which revealed the 5th Bow Latch was faulty.
However I had to get into the storage area first!
The Manual refers to a pair of emergency lock release cables accessed by removing the rear trim in the trunk.
BUT treat these with the utmost respect as (as I found!) it is far too easy to pull them out of their mountings inside the storage area - and when pulled out they are totally unusable for releasing the storage lid locks!
So if/when this happens.. inside the car, remove the left and right hand rear vertical speaker mountings behind the seats (they just unpop off) and use a torch (so you can see!) and a long bar (18" ish, like a socket extension bar) to identify and push back the locking mountings each side.
And reaching between the seats with a 10mm spanner, undo the nuts holding the latch to the 5th Bow. This will give you serious b**l ache and needs a ton of patience and small hands to access the tiny access hole under the rear windscreen!
Inside the car, manually release the front roof lock (remove a plug in the roof moulding, and use an Allen key) before a lifting of both front and back at the same time folds the roof up to allow the storage lid to be opened.
Wedge a piece of wood between the roof 5th Bow and the storage lid to hold both up to access the guts of the mechanism underneath the trim of the storage area.
My issue turned out to be broken wires in the harness to the Locking unit. There are 4 wires - one which is power to the sensors (all 3 share the same power), and 3 returns - 1 from each sensor.
Remove the green plug from the control unit and undo the white harness plug from the locking unit. Testing for continuity between the various pins in the green plug and the white plug revealed a short between the power wire and one of the sensor wires.
Totally remove the harness (no pain here - very straightforward once a load of anchoring zip ties have been cut out) and strip the cloth protection tape. Found 3 wires had their insulation broken in several places, allowing 2 of them to touch.
Re-insulate each wire and wrap everything up again, replace the harness and green plug and check roof diagnostic again - all clear now. So that fixed the button not working.
Bungee replacement time - and found within part of the roof frame (balance link) which carries both hydraulic pipe and sensor cables, more bare wires - where their insulation had been worn off (by something not properly identified). Reinsulated these wires again.
BUT in the Nissan document, Step 65, they specify adding a couple of cable ties around this conduit to stop a new spring rubbing these potentially exposed wires. A properly totally useless idea.
Instead I cut a piece of tin out of an old coffee tin (this was flat and without corrugations) big enough to extend the length of the visible content in the conduit, and wide enough to wrap completely around it (something like 8cm x 8cm or thereabouts). Secured this tightly with the cable ties Nissan expect you to use. Thus my conduit is now completely shrouded in tin plate and whatever was rubbing it before can now do so without fear of further damage to what it is carrying.
Note the attachment of the end point of each 'cable tether' (with the new spring in it) uses a pre-drilled yet unused bolt hole in the frame - almost as if this was the original design but never used (for 9 years). To ease this attachment, ensure the roof 5th Bow is as folded up vertical as it can be, then getting the bolt in the hole is much easier as the cable tether is as relaxed as it can be and the spring is not under tension.
Sadly limitations on attachment sizes prevent uploads of the mentioned documents but there are references elsewhere in this forum. A zipped Service Manual is about 75Mb; just the RF section from it is down to 3.8Mb, and the Nissan technical document about replacing the bungees is about 1.8Mb.