Which is the Top Closed Switch on the latch?

Symptoms are described in Troubleshooting Guide from the Convert Top Tech Bulletin 501-11

On opening the top...."The rear quarter windows will lower; and the top will start to unlatch; but it will only lift slightly and remains in the latch claw. After about 5 seconds the latch claw will rapidly retract and this pulls the top back into the latch.

“Top Latch Fail” will NOT be displayed on the instrument panel after operation

Possible Cause: "Short circuit in the top closed switch"

Also if I insert the allen wrench in the head to manually twist the latch, the top operation will continue operating through its cycle. This made me suspect a switch in the latch was being jiggled.

All other trouble shooting cautions (good battery, fluid level OK, etc.) have been checked.

 

Hi Gordo, have you made sure the 'claw' is freely moving in and out. From your pic, is that score marks on the left, perhaps making it more resistance for the 'claw' to open to its full potential?

 

Gordo,
What have you done this time? I need to read your post a few more times to get what is going on but the TSB 501-11 gives you the switch positions (open/close) in the final status. I guess I should ask do you have the entire TSB? Also do you have a copy of the cars oneline to get locations of the switches? If not you can get it from my page. Give me a little time to re-read what you posted.

 

Hi guys...

There is no bind in the claw; it moves freely in open and closed position. What appears to be scoured marks, is white lithium grease.

The TSB is ten (10) pages and appears complete, e.g. page 10 of 10.

Originally, the top operation was intermittent, then would not open at all. The symptoms were as noted in the original post. These actions coincide with the TSB trouble shooting guide on Page 8, the sixth table down.

AFter removing the header finishing panel, I played around with the switch in the picture, and afterwards the latch seems to work OK. If that switch in the pic is identified as the "Top Closed Switch", then I am pretty sure the problem source has been located and I can keep an eye on it if there is a similar problem.

Currently, the top functions normally. I have also learned to identify when the solenoids switch the hydraulic flow from the latch to the cylinders. Previously, with the switch stuck, I dont think that changeover occurred.

So I am wondering if maybe the contacts were just dirty or the switch stuck, etc.? I am thinking this because earlier, if the Allen Wrench was inserted into the latch and used to 'assist' the hydraulic pressure, the latch would sequence properly. But I was probably jiggling the Top Closed Switch, satisfying conditions for the next function... not assisting the hydraulics.

 

I think that the switch is sticking if the mechanism is not. This has been about the second or third time I heard of this taking place and it might be the beginning of switch failures. Gordo is it possible to get info off the switch to see what might be available or have you put it back in? Also I think when they use the term “short circuit” in the TSB in my mind it means not working, a short circuit to me means blowing fuses or something greater.

 

The header panel has been reinstalled, so I cant identify model numbers or manufacture data.

As pertains to the functional meaning of 'short circuit' in the switch; to you and me it means there has been a broken wire grounded out or a shunt has occurred and is allowing current to flow where it shouldn't.

However, I also agree the TSB could simply be saying that the switch is remaining closed when it should be open. Our British cousins could help us out on interpreting the nuances of this Jaguar-speak.

Just to be clear, I am not referring to the metal tab that teeters up and down, but rather the micro switch underneath activated by the tab.

 

Have you sprayed some WD-40 on the latch mechanism? It solved my problem instantly. I give it a little booster shot about every 6 months.

 

I use white lithium grease and some machine oil on the bearings. Both of which I think have better lubrication qualities.

Edit:
Although after a second thought, if it is the switch sticking, maybe a shot of WD-40 might be a good idea. I'll let you know if that was it. g.