Well I changed all my bulbs to LED except for the headlamps(they haven't made replacements for them yet (I think). And I have the warning light come on when I put on the brakes and everything was working fine until all of a sudden one night my blinkers stopped working when I put on the headlamps. I find out that the blinker lights would light up and stay on with the parking and the headlamps but not blink until I turned of the lights. The emergency lights blink very slowly with the lights on. I know changing the bulbs may have thrown a stick in the spokes for hoping to get any help. But I swear I didn't REWIRE the dam car. And what are these two fuses on the rear driver side that go to a block that connects to nothing? And two more wires male and female one black(male) and one female (I think it's red and green) just hanging down. Anyone got any ideas? Oh yeah, 1991 xjs convertible.....UN.. BE...LIEVE....ABLE! Bud P.S don't tell my car I cursed at it. Pleeeaasse!

 

Check/clean/tighten the ground for all the external lamps.

As I recall the forward lamps ground at the left and right ends of the radiator upper mounting panel and the rear lamps ground at studs at or near the real lamps themselves.

Cheers
DD

 

If you changed the blinker bulbs, then this might have upset the blinker unit itself. I think, only think mind, that the blinker unit relies upon heat in the circuit to make and break the current. So with LED blinker bulbs the current draw in the system is different and thus the heat the unit sees. If the headlights are on, maybe the current available to the blinkers changes sufficiently so that not enough heat is generated?

For example, if you remove a blinker bulb completely, the system blinks oddly or not at all because of this phenonemon - which acts as a warning of a bulb out in that circuit.

If you rev up considerably, you might find the current generated rises sufficiently to start the blinkers flashing, headlights on. The emergency lights going, but slowly, might confirm this idea, as more current is being condumed with all lights going, thus more heat.

 

The turn signals and hazard warning lights rely on the current flow through the flasher unit itself to make and break the circuit. LEDs do not consume the watts necessary to trigger the flashers. There are load devices to put in the circuit to fool the system. Daniel Stern lighting can help you sort things out. I replaced my turn signal, back up lights, and brake lights bulbs with a higher wattage bulb from Honda. Went from 21 watts to 27 watts, and 31 watts in the back up lights. A much needed improvement. The bulbs are nickel plated rather than brass which cuts down on potential socket corrosion.
Superbrightleds dot com may have the load inducers necessary to keep everything functioning. I am in the process of replacing the warning lights above the instrument cluster with colored LEDs. Already replaced my light bulbs in the facelift style trip computer with green standard brightness LEDs. I will find the part numbers for the two size Honda bulbs.

 

If I understand correctly the lights were functioning properly *after* the LED bulbs were installed...."everything was working fine".

Some time later...."all of the sudden one night....." the problem arose.

If I'm correct in my interpretation, the LEDs may not be the cause of the problem described.

Most commonly....not carved in granite, of course....when a circuit malfunctions *only* when a different circuit is used it's a ground issue. In this case, using the headlights makes the signal circuit go wonky. Quite common; not Jag specific.

For example, on my XJS the tachometer would instantly go nuts whenever I turned the haedlights on. The instrument cluster was poorly grounded!

Cheers
DD

 

What would make my blinkers go on with the rear lights (both sides) and stay on like they were parking lights? It's like something short circuited or something or other. This is what is perplexing me the most. A loose ground can cause this? So I connect the ground and they go OUT? Gettin set to put the filament buggers back in to see what happens. Sheeeeeesh

 

I don't know for a fact if a poor ground is causing your problem.

I DO know, however, that a poor ground can make strange things happen.

I would begin by cleaning/tightening the grounds. That's my advice. It's a fundamental step when chasing electrical gremlins. It's no secret.

Or retrofit the old bulbs if you want.

Your choice !

Cheers
DD

 

Just a guess mind, but it might be current backfeeding somehow. Because the LEDs need such a small amount of current, they may be getting it via a backfeed circuit when the sidelights are on.

Greg

 

Hope I didn't come across unappreciative with the (but) thing. Thank you for taking the time and using your brain power for my plight. Taking time out to help strangers is a BIG deal. If I find the solution I'll post it. Again thanks fellas for your time and concern, Bud.

 

Stumbled on this thread while looking for something else, BUT I have a problem that sounds like it MIGHT be related - the oil gauge is behaving weirdly:

When I start the car in the morning the oil gauge flips over to the max position and, mostly, stays there. After driving for 30 minutes or so, it SOMETIMES starts working normally. Sounds like "something" warms up, expands, and connects, no?

If I park the car uphill, leave it for a while, say 30 minutes, and then start it up the gauge works normally most of the time.

Grateful for ideas. B.T.W.: where is the ground for the instrument cluster?

I hjust started another thread, but since that problem might be in the same area, let me repeat the question here:

The row of warning lights above the tach/speedo is so dim it cannot be seen it daylight. Any ideas on how to make it brighter?

Grateful for all suggestions!

 

I found on this forum that you can obtain 5 watt filament bulbs which I believe are higher than the stock bulbs and would be brighter, but I puchased LED bulbs which are Extremely bright and do not produce as much heat AND practically will never ever have to be replaced due to their 50,000 hrs. of life. These leds do not require a resister as in some other applications on the car (IE) stoplamps. Bud

 

Do you have a part/manufacturer number for these 5W and/or LED bulbs?

 

I'll get them. Bud

 

OK, Go to ebay and type in "xjs jaguar instrument panel lamps. Scroll till you see t5 bulbs. They will be selling them in packs of 10. Even though the compatibility chart for these bulbs say they aren't for your car ,they are. I don't know why they do that,(even though it say's "fits xjs").T5 is the key here, that's the size for ALL xjs dashes except for maybe the 93 - 96 models. For the led bulbs type in "t5 dash bulbs. You need the single SMD wedge type. There's all kinds of offers and prices and amounts of them for sale. Look around and decide which is for you.Bud

 

I exchanged my brake light CREE 25 watt brake light LED bulbs for the signal bulbs at the rear which were a multiple led design having them in a 360% configuration to simulate a regular bulb,but I believe they were of a slightly lower wattage value than the CREE bulbs. Well the bulbs now blink! But the bulbs have taken on a dual filament mode. What I mean is that although the led doesn't have 2 filaments it it both blinks and acts as a parking light. It's supposed to go out between blinks but doesn't. Well better than nothing. I'm still experimenting. Now thinking that wattage has a lot to do with these replacements. Bud