I have a 1992 xjs. It has daytime running lights. When I turn the lights on and switch to high beams, I lose all lights. Any suggestions?

 

Hi Gary

If you turn on the lights and get low beam, then go to high and have no lights, the possibilities are:

1. Faulty headlight relay
2. Faulty/disconnected connection to headlight relay
3. Two blown fuses in the high beam circuit

Try flashing the headlight with the lights off. The battery source and contacts in the relay are different for flashing rather than when turning high beam on normally. If it flashes OK this would definitely point back to the relay.

Posting your question in the XJS section would get you more model knowledgeable eyes.

 

Welcome to the forum Garryt,

I've moved your question from General Tech Help to XJS forum. Thids is the place to post technical questions about your model.

Please follow this link New Member Area - Intro a MUST - Jaguar Forums - Jaguar Enthusiasts Forum to the New Member Area - Intro a MUST forum and post some info about yourself and your vehicle for all members to see. In return you'll get a proper welcome and some useful advice about posting to the forum.

Graham

 

I have a 1992 XJS convertible. Randomly, whether driving or standing still, the high beam lights come on and stay on for no apparent reason. I can turn them off by turning on the headlights and then turning the headlights off. Many times, after a few seconds, the high beams come on again for no reason. This has even happened when the car was not running. Any ideas what is causing this?

 

Start by changing the headlight relay. If that dos nothing, you have a wiring fault between the switch (and including the switch) and the relay that is somehow activating the relay.
Greg

 

Thanks for the input.

I got some time today and worked through the circuit. I had the engine running and when i lightly touched the Lamp Control Module on the left hand wheel well, the high beams came on. I could duplicate this time after time - just a light touch and hi beams were on. I removed the module and inspected it closely. The silicone that seals the base to the cap had breached in one place, letting humidity as well as high temps into the can. I removed some tin whiskers on the circuit board, plugged it back in and it worked properly a few times. But, when things heated up it started to again cause the hi beams to come on with a slight touch.

So, tonight I will put the module into some rice and leave it there for a few days to dry it out. Then, I will seal it back to the cover with Silicone and see how it performs.

 

. . . or, simply replace with new.

Just my 2c so don't shoot me but you have done well to isolate & confirm source of fault. Even with your intended DIY fix of drying out, then silicone, you will never be sure how much corrosion damage has been done internally.

Cheers,

Ken

 

I agree with you. But, since the car is not a daily driver, I have time to experiment and see if I can fix the module. If not, I have located a replacement. Will let you onow how it turns out.

 

I ordered a new capacitor and two new transistors and installed them in the module. IT WORKS! Hi and Low Beam Headlights now function properly.

The capacitor that I replaced was an aluminum electrolytic axial capacitor from Vishay PN 211837101E3 (100uF, 40V, 125 degree rating). The NPN bipolar transistors were On Semi PN BC33740TA. Total cost about $5 from Mouser Electronics.

 

Kudos to you for being able to open up the box and replace the faulty components. I wish I knew more about electronics, I'm more the grease monkey type.