I got back to my first "do it myself" project on the convertible top today, and after a few hours of troubleshooting and research, I think I've narrowed it down to the Top Ready To Latch circuit.


Symptoms:
Top comes all the way to the latch (which does pop up properly), but the latch fails to finish the sequence, and I hear what I think is the pump working heavy if I hold the button down for a brief time. Once I turn the car off, the latch does pop quickly down, usually taking the top the rest of the way down with it. Occasionally I have to give a little tug on the handle to seat it all the way. Rear windows never come up with normal button operation. This began after the rearview mirror was removed for the icky goo issue.


What I've done:
Topped of the hydraulic fluid, and after a couple of weeks the level is holding steady. (no fluid anywhere I can see, i checked under the rear seat as well. all dry!)
Removed the trim and had a peek. No visible wear and tear on the hydraulic line or the wires (even looked at the wires from under the overhead light panel... they look fine.)
Reseated the three BPM fuses (none were bad)
Jumped the rear windows to close when the top was up
Tried using that allen wrench to manually move the latch... that either takes more muscle that I've got, or I'm missing something about the operation. I got it to wiggle a bit.


So, the crazy thing to me is that after I reseated those BPM fuses.. which I did with the top down... the top stopped working completely. I pressed the button, no pump noise, no movement... nada. But then the husband hit the little metal switch on the spring next to the latch... and the rear windows rolled up! Then I used the button to roll them down, hit the roof up button, and bingo bango bongo... the roof was raised! But still no completion of the latch/rear window sequence.


I took a look at the STB 501-11 (Convertible Top Electrical System – Component Descriptions & Diagnosis) and I still have a few questions to assist with my next troubleshooting steps.


Is that little lever on the spring next to the latch really the top ready to latch circuit, or is that the top closed circuit? If it's the closed, can someone provide me with some less technical info/links on the top ready to close circuit please?


When the top meets the latch, is it an electrical signal that tells that ready to latch circuit to close, or is something manual happening where the top is physically making contact with a moving part?


In the wiring, there was a blue connector wrapped up with the white wire that seems like it's the top ready to latch communication wire from the latch to the BPM (if I read the STB right), should something be plugged into that blue connector?


Any additional answers to questions I may not have thought to ask?

Thanks again to everyone who has already helped, and in advance to anyone who replies to this message!

Happy Driving!

 

I didn't understand the first comment ' . . . once I turn the car off . . . .'. That doesn't make sense . . . to me.

There are two micro switches associated with the top latch. One advises that the latch is unlatched and to begin to operate the top. The window issue has got to be associated with the one that advises the BPM that the top is completely closed and it is time to raise the windows. Sounds like the top latch ram is not fully operating or it and/or the micro switches are out of adjustment or the switch contacts need cleaning.

 

Have you downloaded JTIS from the first 'sticky' in this section ?
You might as well clean and lubricate the latch mechanism first.
Be careful not to get lubricant in the microswitches.
There's another one on the right raise ram to signal it is fully extended.
If that goes the locking sequence will not initiate.
There's an excellent how-to from Gus here
http://www.jagrepair.com/RoofLatchRepair1999xk8.htm
You can check the switches for continuity with a meter to see if they're behaving as they should.
To use the Allen key you have to open the pump petcock so you're not fighting the hydraulics.
If it is still hard then lubrication is required.
Don't forget to close the petcock FIRMLY clockwise afterwards.
Let us know how you get on.

 

Thanks, Guys!

Test Point - when I have the engine on, and press the button to raise the top, it connects to the latch but won't finish the latch process. When I turn off the ignition, the latch quickly pulls the top the rest of the way down. The rear windows will not raise as I get the Convertible Not Latched error. But I can jump the rear windows closed no problem.

Steve - I've got the JTIS, and have been working my way through it, but find it a little confusing since I'm a n00b at this stuff!

I did try lubing the latch mech, and I'm starting to think I got lube on the contacts, because today I'm getting Convertible not latched in the top down position, and it won't raise back up. Although I made it worse, I'm still happy that I've given it a gung ho try! I'll eventually get to where I can work on the girl myself.

I'll check out Gus's guide this evening, and if I'm still out of luck I think I'm going to have to take it in to the professionals.

 

Check to see if you do not have the hoses crossed at the pump.

 

I'm assuming the top was working fine, you did nothing to it and this just happened out of the blue.
There's no doubt you/we can fix this, you've already demonstrated the practical and logical skills to do so.
Gus is the expert on this and will, I hope, correct me if I'm talking rubbish.
We haven't answered all your questions - I don't know where your blue connector is - can you take a pic?
I believe the sequence of events at the window header when the top is closed are
1. Pressure is sent to the 'open' side of the ram to raise the catch
2. When fully raised the 'Ready to Latch' switch closes
3. When the top latch hits the 'Top Closed' switch AND the main lift ram 'Top Raised' switch close pressure is applied to the 'close' side of the ram
4. When the ram is fully closed it activates the 'Top Latch Closed' switch
5. When 'Top Latch Closed' activates the rear windows are raised.

As you say the process is handled by the body processor module which, contrary to popular belief, is not full of electronics but populated by Djinns and Daemons.

As I see it (provided it was working OK before) there are only two possibilities
1. (most likely) the Top Latch Closed switch is either bad or out of adjustment.
You can check its operation by moving the latch with the Allen key and checking the relevant pin on the BPM which should go to 0V when the switch closes.
2. (Happened to me + some others) The djinns in the BPM have been on the herbal tobacco and got confused.
To unconfuse them get the hood in some rational position (fully up, latch closed manually if need be) then do a hard reset (disconnect batt earth, touch earth lead to batt +ve for a few secs, reconnect earth lead. Make sure you've got the radio codes and have a look at Reset procedure after a battery reconnect in HOW TO at the top of this section.
Then
Lower the hood (I manually unlatched it then used the button to lower it fully)
Then raise it until it locks.
If the back windows don't come up and you still get the Top Not Closed then it is the switch or wiring.

 

I guess I did jump the gun I thought this car was another car that had changed the hoses. The roof latch not working properly could be a number of things and a little more info is needed to figure it out properly. For now I would not be hunting down an electrical problem. Check your PM

 

LMK -

In the event you're still stuck, here is another reset procedure you might try. This is similar to the one suggested by Steve, but differs in that we take the top from a fully-closed to fully-open state without using the car's control system in any way (except for lowering the windows). I copied this verbatim; the terminology is rough but I think clear enough for us as this point.

To reset the system, press the top switch and lower the quarter windows.
Open the valve on the trunk, counterclockwise.
Release the top latch with the allen wrench.
Push the top cylinder pistons back and down until they go over center, about 2 inches.
Lower the top completely by hand.
Close the top latch with the allen wrench.
Close the pump valve and press the top up switch.
It should go up and latch. If it doesn't, there is a permanent problem.

The originator is a professional Jag tech so it's possible he knows things we don't. Probably worth a shot if nothing else has worked so far.

If the part about pushing the rams "over center" is not clear, ask before going forward. It is possible to damage the top by trying to manually lower it without using the proper procedures.

Good luck.

 

Thanks, Dennis! I was coming onto the forums today to look up the manual top operation. I have the JTIS so I can look up to see where exactly to put pressure to move those rams.

I did end up taking it to my auto place (which I'm thinking may not be my auto place much longer) and they are saying that there is air in the hydraulic system and that the positioning switches aren't working. They did try and use the (I forgot to write it down!) electronic device that they can plug in and get error messages back, but it didn't get back any information. They want to charge me another 5 bills JUST to continue troubleshooting... so I'm having them put her back together and I'll see if I can continue, and/or get another opinion. Once I get the diagnostic report from them, I'll know more.

I know there are guides out there for bleeding the air out of the hydraulics on the roof... a friend suggested I ask if I can use a bleeder (like is used for break lines) to get the air out of the system? Since the auto shop said there is a 'lot' of air in the hoses, would it be beneficial to go ahead and flush out the hydraulic system?

I probably won't get a chance to work on her again until this weekend. Thanks everyone for your continued support!

 

The roof system will self bleed it has no process for bleeding the system other than fill the system to the top line and operate it a few times and check it again.

 

As for the piston switches if your windows go up and down they are working. Check your PM.