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GM Press Release Does Anytone Really Understand the Roof Top Operation?

Tinker

Active Member
Joined
Apr 8, 2016
Messages
32
Location
North Bend
My XLR/V(s)
2004 Zenon Blue XLR
Hi From the beautiful Oregon Coast,

My 2004 XLR's top stopped working mid cycle. The trunk lid wouldn't go down while opening the top. Since it wouldn't go down I hit the Up switch. The hydraulic pump ran, but the trunk wouldn't go up. Noticing that no matter whether the Up switch was pressed, or the Down switch was pressed, the trunk lid just dropped just a little, so opening the valve on the pump, the top was opened for the drive home. There is a procedure for raising the top manually, but it never mentions that an 8MM hex wrench is required (along with skinny forearms). This wasn't fun, but the top was raised to prevent the rain from ruining any future trips.

Since the trunk dropped no matter whether it was requested to raise, or lower, it appeared that the problem was either the control module, or the Pump/Solenoid Assembly. Inspecting the control module revealed that the board was conformally coated to make it waterproof, and there were no visible signs of component damage. The pump assembly was sent to Klaus at Top Hydraulics for repair. Klaus is a very nice and knowledgeable person. He exchanged my pump for a rebuilt one on the spot, asking if I would return with the XLR once the top was functional so his crew could see its operation for themselves.

The pump assembly was reinstalled. With high hopes and a smile the Down button was pushed. The windows lowered the proper amount; the trunk lid fully opened; front tonneau cover raised, the roof assembly lowered into the trunk, but apparently didn't fully latch, and there things ground to a stop. The up button was subsequently pressed. The roof assembly raised back into position, but didn't fully lock. Opening the valve on the hydraulic pump allowed the roof to be fully closed with the aid of the aforementioned hex wrench. Subsequently closing the valve and pressing the Down switch the roof assembly was raised for inspection to the mid positon. After a few minutes the Roof Assembly slowly dropped to the closed position. The valve was fully closed, which meant the hydraulic cylinders which operate the roof assembly were leaking. A leaking top latch cylinder was the likely culprit in not fully locking the Roof assembly as well, since the fluid level was normal.

There are seven hydraulic cylinders that operate the top. Three on mine are proven leaky, so apparently it's time to have all seven rebuilt. Does anyone have any experience with removing them?

Some of the problems were discovered with the aid of a Tech II. In real time mode it showed the Trunk lid position sensor (potentiometer) was loose so the limits weren't consistent. Other threads have pointed out the poor single screw mounting point which invariably will loosen causing operational failures. A spare sensor will be located and disassembled to find better method to fix this problem. The fix will be shared, but the other two potentiometers must be located prior to fixing the mount. Does anyone know where they are hiding? Has anyone replaced them? Any Tips?

Someone mentioned updated software should be installed in the Top Control Module. Does this exist, and if so where can this be found? Has anyone updated their software? In stating a software update was needed did this actually mean doing a re-learn procedure? Does the programing in the Top Control Module allow for position tolerance, or must the limit values exactly match. In example the potentiometer position value can be between 0-255. Lets say that in operation the current low limit required is 110. If the position sensor goes past this value to 105 does the program recognize that the sensor has fulfilled the requirement and proceed to the next program step, or does it require an exact match? Or does the program stop the operational step once the sensor matches the programed value of 110?

All of these details matter when you are trying to understand just how and why the top operation works. Once you understand then making changes to add reliability to the operation can be accomplished. This just means I'd like my top to reliably go up and down as intended. :)

Removing and reinstalling the pump assembly takes a bit of effort so pictures are included for those who are curious.
 

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Tinker

Active Member
Joined
Apr 8, 2016
Messages
32
Location
North Bend
My XLR/V(s)
2004 Zenon Blue XLR
This is NOT a GM Press Release

If you know how to correct this error please let me know.
 

ccclarke

Seasoned Member
Joined
Sep 17, 2008
Messages
1,032
Location
Uncanny Valley, New England
My XLR/V(s)
2013 Graphite Metallic XTS Platinum
Hi,

I bought my XLR in North Bend (WA.)

The majority of your questions have been covered previously. You have access to a Tech 2; do you own a Service manual? One is nearly worthless without the other for top-related issues. Cylinder removal, top-relearns, sensor locations, etc are explained in detail in section 8. The same outfit that re-builds pumps works on hydraulic cylinders too. Ensure you replace all O-rings with fresh ones if you disconnect any lines.

The pot mounting scheme is flawed. They must be epoxied in place after the (single) fastener is installed to prevent the body from moving. Digital encoders would have been the way to go, but the FTC module uses voltage to determine start/stop positions.

Picture #4 of the pump reinstall shows the pump/reservoir at a 90 angle. This has the potential to introduce air in the hydraulic lines. Not good if it occurs.

The 8mm wrench (or special double-ended allen wrench top tool originally supplied) has been written up here extensively. There's a wealth of information here to answer the title of your post.


CC :wave:
 
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ccclarke

Seasoned Member
Joined
Sep 17, 2008
Messages
1,032
Location
Uncanny Valley, New England
My XLR/V(s)
2013 Graphite Metallic XTS Platinum
If you know how to correct this error please let me know.

To verify the header latch isn't fully engaging when the Folding Top stows in the trunk, try opening the rear deck lid and removing the fabric cover (not installed in later models) on the front trunk bulkhead. Then remove the center console (above the armrest) and with the aid of a flashlight and inspection mirror, lower the Folding Top. When it stows in the trunk, verify the latch "fingers" engage the post. Also the header latch counts should closely match the expected counts. If you haven't already, create a chart of all position counts for raised/stowed sensors to aid in further troubleshooting. If most position sensors are operating, use their count info as a baseline.

The last Folding Top update increased the allowable tolerance for the (three) position sensors to increase the reliability of the mechanism. The info (including latest rev which can be loaded from a Tech 2 if its 32Mb PCMCIA card is current --being a relative term, since the last software update was released years ago) is archived here somewhere, but position tolerances are called out in the Service manual. The position sensors do seem to wear out over time and you'll note the majority of reported failures are attributed to them. The sensors only report the position of the top, (located behind the driver's side sail panel vinyl) front tonneau (center of forward trunk bulkhead) and rear tonneau (rear deck lid / left side cantilever lift mechanism.) the rear decklid and header latch get their status from switches. The Top Secure indicator is controlled by a micro-switch located in the windshield receiver on the right side when the positioning pin engages.

Hope this helps a bit,

CC :wave:
 

dennis93coupe

Seasoned Member
Joined
Mar 3, 2014
Messages
174
Location
Orange County, California
My XLR/V(s)
2009 XLR-V Crystal Red with Ebony / Cashmere 1 of 6
To verify the header latch isn't fully engaging when the Folding Top stows in the trunk, try opening the rear deck lid and removing the fabric cover (not installed in later models) on the front trunk bulkhead. Then remove the center console (above the armrest) and with the aid of a flashlight and inspection mirror, lower the Folding Top. When it stows in the trunk, verify the latch "fingers" engage the post.

CC :wave:

There are two cables connecting the header latch mechanism to a latch mechanism on each rear side of the roof, those latches can be verified latched to the pedistals that hold the trunk divider.
 

Tinker

Active Member
Joined
Apr 8, 2016
Messages
32
Location
North Bend
My XLR/V(s)
2004 Zenon Blue XLR
Thank you for answering. Which Posts discuss these problems? Searching for Top Operation, Top Failure, or Top won't Open didn't yield any satisfactory results. Any suggestions?

Yes, I own the Service Manual, but sometimes speaking with an experienced technician is beneficial. I'm planning on removing all the cylinders and having Klaus rebuild them. Epoxying the sensors in place doesn't allow for easy replacement in the event of failure. A mechanical modification might provide both serviceability and functional operation.

Doing a top relearn procedure (as is often suggested) requires a the top to complete a full cycle both up and down. At work I programed many remote terminal units (RTU) with analog limit logic. The FTC module programing limit logic would be nice to understand.
 

David_B

Seasoned Member
Joined
Aug 31, 2014
Messages
446
Location
SE Michigan
My XLR/V(s)
N/Z
If the button to raise and lower the top doesn't work, that doesn't mean a re-learn will fail. If you didn't try one, I would.
 

ccclarke

Seasoned Member
Joined
Sep 17, 2008
Messages
1,032
Location
Uncanny Valley, New England
My XLR/V(s)
2013 Graphite Metallic XTS Platinum
There are two cables connecting the header latch mechanism to a latch mechanism on each rear side of the roof, those latches can be verified latched to the pedistals that hold the trunk divider.

Not sure what you mean. The pedistals in the trunk are only meant to support the cargo divider when it's raised. The left side has a micro-switch that will disable the Folding Top cycle if it's open (no luggage barrier installed.)

The two hydraulic lines to the header latch inside the roof panel are to open/close the Header Latch via Hydraulic Solenoid #1. The Header Latch uses one hydraulic cylinder (as does the front tonneau.) All other hydraulically-operated top components use two cylinders. The Rear Deck Lid has a pair of little pneumatic-assist cylinders hidden under the rat fur on the sides of the trunk. A pair of micro-switches in the latch assembly signal if it's open or closed to the Folding Top Control module.

When the Header Latch closes in the Raised position, the roof will dip slightly. It also snugs the rear/lower section of the roof against a pair of pins on either side. In the trunk, the latch locks the roof to a vertical pin so it doesn't flop around. This is what you can check out by removing the center console. (That's an easy removal too.)

As for related threads, note that many folding top-related threads may be address an initial problem, but others, will add new problems within the thread, so you really have to read every post to get the most out of each thread. It can get confusing and disorganized sometimes, but there's a wealth of information contained within if you can make the time to read through them.

I'm on vacation (Seattle here I come!) starting tomorrow for two weeks, so I might not be posting as much. (So much beer, so little time!!)

CC :wave:
 

dennis93coupe

Seasoned Member
Joined
Mar 3, 2014
Messages
174
Location
Orange County, California
My XLR/V(s)
2009 XLR-V Crystal Red with Ebony / Cashmere 1 of 6
Top latches

Not sure what you mean. The pedistals in the trunk are only meant to support the cargo divider when it's raised. The left side has a micro-switch that will disable the Folding Top cycle if it's open (no luggage barrier installed.)

The two hydraulic lines to the header latch inside the roof panel are to open/close the Header Latch via Hydraulic Solenoid #1. The Header Latch uses one hydraulic cylinder (as does the front tonneau.) All other hydraulically-operated top components use two cylinders. The Rear Deck Lid has a pair of little pneumatic-assist cylinders hidden under the rat fur on the sides of the trunk. A pair of micro-switches in the latch assembly signal if it's open or closed to the Folding Top Control module.

When the Header Latch closes in the Raised position, the roof will dip slightly. It also snugs the rear/lower section of the roof against a pair of pins on either side. In the trunk, the latch locks the roof to a vertical pin so it doesn't flop around. This is what you can check out by removing the center console. (That's an easy removal too.)

As for related threads, note that many folding top-related threads may be address an initial problem, but others, will add new problems within the thread, so you really have to read every post to get the most out of each thread. It can get confusing and disorganized sometimes, but there's a wealth of information contained within if you can make the time to read through them.

I'm on vacation (Seattle here I come!) starting tomorrow for two weeks, so I might not be posting as much. (So much beer, so little time!!)

CC :wave:

Once again, there are two cables connected to the header latch mechanism. One cable to the left rear latch, the other cable to the right rear latch. Those rear latches latch onto the rear pedistals in down position ALSO. Photos included of right rear latch. This is what keeps the top from flopping in the rear when down.

Passenger side rear latch...


Passenger side pedistal, notice grommet to the left of the bumper and the divider on the left. This is viewed from the rear of the car.


Top down and latched.



Now if you will notice in this photo, (Hope you don't mind Luke), the cables going from the header latch to each rear latch and in the top of this photo the hoses going to the header latch cylinder.
 
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