370z roof issues

AndyJ370z

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.

Red Voodoo

The roof on the Z Roadster is great until it isn't. When it fails, it seems like you're screwed unless it's either under warranty, you're made of money, or you have the skillset to fix it yourself.

My prior experience with convertibles involved first and second generation MX-5 Miatas. I loved the fact that I could easily reach behind me to bring the top down or raise it back up. I miss that. It wouldn't be so easy with the Z with everything that's in the way, but I'd have no problem getting out of the car to manually operate it if it was an option.

I've said it before. If my top quits working (which seems inevitable), I'm going to pay what I need to get it under the tonneau cover and just keep it that way. It's almost paid for, and it's not my daily driver, so I can avoid getting wet. It's too bad that this model car has had this common flaw.

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gbhrps

AndyJ370z and Red VooDoo,

As I've stated here over the years, Nissan and all other brands have discovered that they sell so few convertibles that their service techs never get enough experience servicing them to become competent. Its not like changing a water pump, and can take hours of service manual reading to even begin to understand where to begin.

Dealerships don't want the head aches of customer complaints and call backs so they have one solution for all top issues ... a complete top mechanism replacement at $13 000. Check out Ferrari. They charge $35 000 for their top replacements. All other manufacturers have gone the same route. MX5 Miata's start looking pretty good at that stage ... if you fit the car. At 6'3" I unfortunately do not.

So .. using the roadster service manual and Top Hydraulics YouTube videos and a DIYer attitude is the way to go if you don't want to break the bank and keep your top working.

Thanks for sharing guys!!

Gene

Elkano

I had issues with my 2010 top.
Dealer wanted $4,290 to fix it.
I wasn’t willing to pay that especially since my 370 is only used when the weather is nice with the top down most of the time.
I did some researching and made it all manual now.
It takes me about 1.5 minutes to open the top however I keep it open with a cover inside the garage.
It may take me 2 minutes to close it.
Well worth the effort.

THE BULL

Last year I saw my buddy do a full top install under warranty.

Straight from Japan the unit was $19,000

2string1

How do you manually close it and lock it in place?

Red Voodoo

I've manually operated the top in a pinch. I haven't tried locking it with the top up (the instructions are in the owner's manual), but I manually put it down when the thing just quit working in the middle of nowhere (Baker, NV). I couldn't figure out a way to lock the tonneau cover, but it does seem to not move even under highway speeds. There is the dash alarm and warning light, but that I understand can be temporarily disarmed by pulling a fuse. I'm interested in Elkano's method if they are willing to share.

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Rodd

[QUOTE=AndyJ370z;3998575]Had for a while the 5th Bow hitting the storage lid - now a known issue as the bungees

Great write Andy, thanks ks.

Elkano

Took me a lot of researching and thinking.
Will do my best to summarize.
1. First need to break loose the top.
2. Two locations, 1st bow, there’s a pop clip by the dome light switch. Pull it with a small flat screwdriver and using and Allen wrench with a quarter turn open the latching mechanisms.
3. Fifth bow, and this is kind of tricky, using a 12mm flat wrench, if I remember correctly, from the inside of the car reach under the rear window and loosen two bolts holding the latch in place. For this you need to remove the pop flops on that cover mesh. It’s pretty tedious as there’s not much room to turn the wrench and a closed wrench won’t fit over the bolts. You need to use the open wrench and turn it bit by bit alternating them. Once you are done with that the latch will still be attached to the compartment hatch where the top is stored.
4. Now you’ll notice that all bows are tied together so grabbing the first and fifth will collapse the whole top. Here I used and bungee cord to keep it tied and out of the way towards the front.
5. Open the trunk and remove the pop clips and cover trim panel behind the top compartment. This will expose 2 SS cables. Pull them using a screwdriver to protect your fingers. Pull the right wire to the left and the left wire to the right to unlatch the system that keeps the top compartment lid closed. In my case it wouldn’t release. And believe me I tried hard. So I removed the trunk lid to reach into the compartment lid hinges and loosen them. Once I did that I pulled the cables some more until they released the latches. I was very happy at that moment.
6 Open the lid and remove the 5th bow latch by disarming the hydraulic bar from it. Pretty easy to do. I wish I had a picture.
7. I removed all that mechanism from that lid at once and now I open it and close it manually.
8. I am not muscleman and can open the top and close it by myself Im about 2 minutes.
9. I don’t drive my car with the top up too much but for when I do I devised a system with a cable to tie down the fifth bow to the trunk. It’s no too elegant but it works fine.
10. So if you want to drive with the top up you need to lock the 1st bow with the Allen wrench. Like reversing step 2 above. That in itself will push the 5th bow down pretty good. Driving over 65ish mph you will notice the top will very slightly lifts at the 5th bow. That’s because of the speed and pressure difference between the outside of the top and the inside of the car. You can either crack the windows just a bit to equalize the pressures or tie down the fifth bow as I mentioned on step 9. Did I mention I am a mechanical engineer.
11. Anyway I love my car but didn’t want to pay the dealer all that money if I only drive the car when the weather is good.
12. Driving with the top down there is no issue as the compartment lid slides into a series of chutes and at 99mph it will not even move.
13. The procedure for opening and closing is exactly as what the car does when working. To hide the top you’ll need to loosen the 1st bow. Loosen the 5th if you have it tied down, collapse them and push them to the front. Open the compartment lid. Keep it open with your shoulder and drop the top into the compartment. Then let go of the compartment lid and it will slide on its own.
14. Obviously reverse those steps to put the top up again.

Hope this helps as I too like to keep all Z’s running.

Elkano

5th bow tie down.
1. I bolted the latch to the 5th bow back again (you will need it). Still tedious but with the top collapsed it was not as tight quarters as it was to loosen it.
2. I used 2 SS wire ties to rotate the latch 90 degrees.
3. Bought a flat steel spring latch-hook (2") and tied it to a steel wire 1/8" about 3ft long.
3. The grommet that remains on the top compartment lid is big enough for the original latch however the two SS wire ties are a bit wider and since they are rotated 90 degrees I cut the grommet opening to make room for them.
4. Inside the trunk I cut down a 4" slot right were the release wires once were located. This is metal so I formed the edges to avoid the sharp metal to cut me or the wire.
5. 6" below it I bolted (against the metal - inside the trunk) a tie down point.
6. Inside the top compartment there is a liner. This liner is kept in place with pop clips... later I learned the liner will get in the way so I tell you now.... I doubled the amount of clips in the center area.
7. So I ran the wire in between the liner, pull it out into the trunk via the opening into the tie down from step #5 above.
8. The hook on the other end of the wire will be latched to the SS wire ties on the 5th bow. Then I pull the wire inside the trunk and tie it down with a small ratchet tie down.
9. Sounds like a lot (and it is) but when you are done without tying the fifth bow it make take 45 second to open/close the tonneau cover. add 30 seconds if you want to tie down the 5th bow.
9. So... when I want to tie down the 5th bow... I tie down this spring hook thing.

Just sharing what worked for me and my 2010 Z.

IMG_E2905[1].jpg

Red Voodoo

Great write ups, guys! This thread is worth a sticky status in this section due to the unique top problems that we Roadster owners encounter. I'd hate to see this get buried. Subscribed!

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