Hi all,
Just a quick question. My intermittent wipers are very erratic wiping anywhere from half a wipe (stopping straight up on the screen) to its full two wipes stopping where it should. Time delay between wipes is also all over the place pausing for up to a couple of minutes.
Normal and fast both work as they should.
Anyone come across this before?
It's not all that important since the only time she gets wet is when she's washed

Cheers,

 

There is a fuse under the kick plate on the passenger side that has probably blown. Common issue with these. Use the search function here and I'm sure there is actually a pic of it. If you get under there you will see it, check that first.

 

Valguard,

Yes, the problem may be with the fuse which is worth checking first. If you find that replacing the fuse doesn't fix the problem then the problem will be with the micro switch which senses the position of the wipers and sometimes wriggles out of proper alignment. This switch is located inside the wiper motor housing which you will find under the bonnet at the base of your wiper, on top of the actual wiper motor.

Easy to get to, and no need to go dismantling everything. All you need to do is undo the four screws to remove the top plate/cover. (no need to remove the whole assembly). Inside you will see a little black (sometimes brown) electrical component with a small button (switch) in alignment with the cam on the wiper. This is the micro switch. Just loosen the adjusting screw a little and move the switch slightly so that it has proper alignment with the cam. Then check wiper function. If needed adjust again. Replace cover. Problem fixed.

There is a paper gasket between the top plate and housing that will probably tear when you take the top plate off. If you do it gently then it won't get too damaged and a bit of liquid gasket maker does the trick upon reassembly rather than trying to find and buy a new gasket.

Very rarely, the switch itself may be faulty. Easy way to test is to press the button and make sure you can hear/feel it 'click' when you press it. If you need a replacement, best to find one off a wreck or get one from a jag dealer (preferably aftermarket as the OEM ones are damn expensive).

 

Great write-up, I need to perform that adjustment as well.

Sometimes the wiper will wipe fine, other times (usually when it's raining hard) it stops mid-wipe, and I have to manually pull the switch toward me (single swipe feature) until it's parked.

The intermittent wipe function depends on that microswitch. During intermittent operation, the CPU will send out a short ground pulse to the wiper relay, just long enough to get the motor moving enough to release the microswitch. Once the microswitch is released, the wiper will continue to run until the cam closes the switch again. As you can imagine, I'd rather have the microswitch stuck closed rather than open, otherwise the wipers will never turn off, as they never receive a "parked" signal from the microswitch.

Nick

 

My wipers are exactly the same. Thanks for the heads up chaps I will give mine a go.

 

Thanks jagfix88, very helpful bit of information it worked a treat.
Mine wasn't quite as simple as that though. While I was talking off the metal cover I noticed a ding in the cover where it had been hit with something by someone. After taking it off I saw it was directly over the microswitch. With a bit more investigation I found it had pushed the switch through the plastic base the switch sits in. Someone had tried to fix this by turning the switch a bit so both the power wires were on the same side of the wire separator instead of one on each side and they had stuck a piece of plastic on the switch to try and hold it there.
I took the plastic base out and realigned the crack flattening it out to be the same flatness as it should be. I then cut a piece of clear, thin, flat plastic (from the side of a cordial drink bottle) to the same shape as the under side of the base plate, then glued it to the under side of the plate with loctite 401 (one of the stongest "super" glues around) and held it flat and in shape till it dried. I then filed smooth the area the switch sits in and the edges of the clear plastic bit to take away any catch areas. I then regreased the worm gear and cam then put the plate back in the wiper motor and put the microswitch back in its proper place and tightened down tthe adjuster screw. I then lifted the wiper of the screen and turned the wipers onto intermittent which didn't work. I loosened the adjuster and moved it till they were working as they should and tighted down the screw. I tested it a few times at all speeds (high speed flicks the wiper back onto the screen by the way) to see if it was working properly whick it was. After taking the extra pit of plastic off the actual switch and a bit of panel beating on the cover plate to but it back into its proper shape, some gasket goo to reseal it and the wipers are working again as the Jaguar gods intended.
One more little fix taken care of, now onto the next one or maybe drill those holes in the bonnet to fit the newly acquired flying D

Valguard

 

Well done!