Drain the Swamp and Count the Alligators
Occasionally the customer has more confidence in you than you do yourself.


The old farmer tells his hired hand,
“Get down there and drain that swamp today.”

The hired hand says,
“Looks like there’s a heap of alligators in there.”

“Don’t ya never mind about them gators,
you just get that swamp drained!” the old farmer explains.

Some days I feel like the hired hand.  I’ll get a job in,
and I already have the feeling there is going to be a whole heap
of alligators between me and draining that swamp.  This time
around it’s a 2004 Nissan 350z with a non-functioning
convertible top.  The top was up, but wouldn’t move,
other than unlatching the rear (5th bow) window section of the top.
 
Jim is an old customer who loves his little Z car,
and was well aware of a few of the alligators lurking under
that deck lid.  How did he know?  Easy, he already tried to
get it repaired at a convertible top shop, but they weren’t up to the task of taking on this alligator infested swamp.
 
Jim’s only comment to me was, “I don’t care how many problems you find, just get it working for me.” 

After gathering all the TSB’s, wiring diagrams, procedures, and any other bits of info I ventured out into untested waters to see what I could find out. All the test procedures started out by checking pin-out voltages and resistances at the convertible top ECM, and guess where that is?… under the very same deck lid that isn’t moving… hmm, imagine that.  The trunk is the only option.  You’ve got to crawl in there and find the cables to release the deck lid manually. 

You could tell somebody else had already been working on it; the emergency cables were nowhere to be found.  I looked like some sort of contortionist trying to get down into the small little opening at the bottom of the trunk with my bore scope. I had to wiggle it around in there, until I found the very thin wire cables that would release the latches. (They were pushed back under the lining of the storage area, which is not accessible from the trunk area)  Ugh, I haven’t even moved the top yet and I’m already swimming with the gators… what could be next?

Once I got the deck lid up I could then remove the interior trim and test the ECM to see what needed to be done.  The output voltage for the 5th bow actuator motor was coming out of the ECM, so unless the wires are broken or disconnected the motor must have failed.  Ok, now crawl out of the storage area and wrestle my way into the passenger compartment, then pull the trim piece on the back window up to expose the 5th bow motor.  The motor brushes were shot.  Lucky for Jim, I just happened to have some brushes that were a perfect fit.  Might as well replace the brushes and see if it will work.

I gave it a try.  With a flip of the control button the 5th bow swung up into perfect upright position, but the top wouldn’t move.  What now!?!?  Back to the ECM and check the stop switches and motor voltages to the top.  This time the alligator is in the ECM. Inside the ECM I found the circuit board lead to the top motors was burnt in two. Ok, fix the circuit board and try again.  The top moved smoothly through its folding process.  As the top closes the 5th bow actuator has to rotate in the opposite direction, so it will sit flush inside the convertible top storage compartment.  As the bow moved to its next position the whole thing quit again.  Oh come on… enough already… more alligators?!?!   Yes, more alligators.  Another trip back to the ECM, this time I found the stop switch for this position wasn’t working.  Somebody had bent the micro switches so far out of whack there was no way most of them were ever going to work.    By now I’ve called Jim at least a dozen times to keep him informed of what I was up against… his only answer, “Keep draining the swamp” Ok, Ok, I got it… I’ll put my waders on and crawl upside down and sideways to get this thing working… but…man these alligators… they’re everywhere.

If you counted the different movements from completely up to fully down there are 12 separate electrical/mechanical operations the top has to go through, AND they all have to work in the correct sequence.  One micro switch out of position and something else begins to move at the wrong time. 

I thought I was done with my alligator counting by the time I had the last micro switch in place, but the first time I got the top to fold up and drop into the storage area, it would stop about an inch or so from completely going down.  Seriously? More gators on the prowl?  What did I miss this time?  I went thru all the electrical and mechanical diagrams again… Nothing, every step was correct, but there had to be something missing.  Then I found the answer on one page.  One short reference to some elastic straps that connect the 2nd bow to the 3rd bow.  These straps spring the 2nd bow towards the rear of the car to allow for clearance, so the canvas and all the linkage arms can drop that last inch or so into the storage compartment. 

I did some more searching and found the part number 97150-CE01B “strap, elastic, convertible top”. I called the dealer and gave them the number…

“Yea, it’s a good number, but we’ve never sold any.”
 
I’m shocked. From what I found out lots of these convertible tops had the same problem. I figured they would have changed hundreds of these.   It looks like it’s a common alligator in this part of the swamp; seems to me every top should probably have these replaced with the new part number, (know somebody with one?… give them that part number). 
 
“Well, get me a set of them.”
 
Once the parts came to the shop, installing them was a piece of cake compared to everything else I had to do.  At least now I could see the bottom of this swamp.  No more alligators, no more swamp to drain… I’m done. I found 20 different problems in the top mechanisms and electrical components.  That’s a total of 20 alligators that were lurking in this swamp. What a job!

It took a lot of effort to solve all the problems that I found. It didn’t matter much to Jim how many things needed taken care of, the smile on his face as the 350z top worked like new made all that gator wrestling worthwhile.  I almost gave up on it several times, but Jim insisted that I keep at it… I’m glad I did. 

So the next time I take on one of these gator infested jobs, I know exactly what I’m going to do.  Ignore the difficulties, and do just like the old farmer told his hired hand to do.

“Drain the swamp, and don’t pay no mind to all those alligators”.