My 1998 XJ-8 does NOT have rain sensor, but recently started turning on the wiper for a single swipe at random times. Once in a while maybe two swipes in a row. The wipers work fine as far as I can tell, and I cannot seem to initiate this problem by tapping on the stalk so I don't think it is in the switch. The other evening this happened and the headlights now go off when the wiper makes its swipe. Quite unnerving ! Sometimes the wiper will stall for a second on the passenger window before it returns to its normal resting spot below the windshield. I have tried tapping on the wiper relays, but nothing happens. My thoughts are maybe something shorting in the wiring near the steering column ??? Often the wipers will swipe after I have used the turn signals and completed a left or right turn, but again I can't duplicate this by moving the steering column or using the turn signals. The battery is relatively new ( about a year old ) and my volt meter shows 14 volts when the car is running. I tried resetting the computer, but the problem persists.

 

No bloody idea what that is, but a good first step if the issue is consistent (ie. lights always go out while wiping) is to try pulling fuses/relays for the affected parts (wipers/lights) and see if anything changes.

Instead of tapping on the relays, swap them with another of the same color and see if the problem persists.

 

Very similar thing was going on in my 98 XJR; water was leaking in through the passenger side cowl (seam that joins into the firewall), some how migrating into the BCM (body control module). Lights and wipers would randomly turn on/off as the BCM was shorting out. Wet padding under the carpet (could not tell by touching the carpet had to lift it up) was present and during fits of electrical rage locking system would not work (another BCM controlled function). used POR15 seam sealer and cleaned the BCM connector(removing the silicone seal on the bcm pins reviled the water) + added Dielectric grease. No more leaks or BCM issues. The common thread with both the wipers and lights is the BCM, there may be a possibility of shorting wires on the steering wheel stalks (common issue).

 

Thanks for the suggestions. Last night the same thing happened..after driving the car to a local shop, upon returning home , the wipers swiped about 5 times and the headlights went out in unison.

 

I had the same issue; it was the BCM, and it was cured by running a separate ground wire down to the gearbox. There is a thread about it on the forum somewhere. My wipers would not only do a random series of sweeps but would also sometimes stop in the middle of the windscreen - most disconcerting. Not only would the headlights go out but all the instrument panel lights, indicators and just about anything else electrical.

 

WOW !
Thanks Nigel. If you get time, I would appreciate more information about this grounding issue, or a redirect to the thread you mentioned. I suspected a problem in the steering column harness or the BCM. I do have the wiring diagram for the XJ-8 for reference.

 

Sounds like a broken ground wire in the multifunction switch. Pull the electrical diagram from the stickies: you will see which wires control the lights and which the wipers. Most likely a broken wire or loose solder connection.

 

This is the thread Wiper randomly wipes one time

 

I actully have a electrical systems guide and electrical system diagram if you still can't figure something out then sorry to say but your car is possessed.

 

If you look at the dates on my earlier posts, you can see this problem has been going on for over a year. For months, I had not a single issue, then all of a sudden I began getting random wiper swipes again. Today, I removed the glove box, and added a ground wire from under one of the nuts securing the BPM unit to a star ground point on the passenger side console area. I removed each nut holding the BPM and sprayed corrosion X on the threads and re tightened the nuts. I also sprayed Corrosion X on all the ground wires making the common connection on the passenger side console, plus I did the same to the ground points adjacent to the battery in the trunk. I will report back soon.