When I either use the key or the button on the console the quarter rear windows go down, i hear the pump run - it tries to lift but it seems that the front latch maybe hangs and then the pump kick out. After a couple attempts it will work. Whats failing?

Fluid is full and I have a new battery.

 

I have the same symptoms. It is a faulty micro switch in the top latch mechanism.

Try pushing up on the top header as it reaches its highest point of retraction... just before it hangs and recycles back to zero. You don;t have to force anything, just give the header a hard push when you see the claw retracting back to its fully open position. You can also use the allen wrench in the manual override the switch in order to fully disengage the claw. This 'pushes' or forces the sequence into the next phase of operation; which should progress without incident.

Note the closure sequence is unaffected by this microswitch and my top closes w/o issue.

The diagnosis of the problem is that the switch is not activating when the 'claw' latch has fully extended. The computer needs to know the latch has fully released the top, so it can instruct the cylinders to continue with the top-down sequencing. Pushing up on the top, or overriding w/ allen wrench, moves the cycle through this part of the operation in spite of the faulty microswitch.

This micro switch is one of three (3) in the latch mechanism used by Jaguar to operate the top latch.

 

I'll take a guess....

After I bought my car last year I noticed the passenger window was a little tight. When I closed the door (with the window up) it sometimes had trouble going up that last fraction of an inch because of the tightness.

After I installed the pressure reducing valve this issue produced another symptom. When I lowered the top with the windows up, the tight window had enough pressure on the top to keep it from going down. I thought my pump was broken. After I figured out what was going on I lowered the window before I lowered the top. The top works perfectly every time now.

I know Sam has a video about how to adjust the window. I haven't done it. The car has a Select Edition warranty. I wonder if stuff like this is covered?

Try lowering your front windows a little, then lower your top. See if it works. Let us know.

Jack

 

Jack, in my car, the main windows automatically drop their normal 1/2" or so before the top starts to open...yours does not?

 

They drop a little automatically, but the window is still touching the top after the drop. Enough to hold onto it when you try to drop the top. This failure to drop enough to be completely off the top MAY be due to the window being too tight as I mentioned previously.

Jack

 

so if it is this micro switch issue what can be done to fix this problem? what parts, how to replace, labor time?

 

Let me know when you find out. Gus has done some work on these, but I don't know which switch it is, or its availibility. Removing the header to get to the latch is not a big deal. However, for now I am OK w/ pushing the header to move it through the cycle.