One of the marker bulbs within my high-beam headlight reflector burned out. I bought standard replacement bulbs but saw that an LED version was available and bought two to do a change-over.
All went well and the LED's are very bright and their whiteness exceeds that of the halogen headlights.
I also had a pair of LED taillight towers from one of my other vehicles that fit the XJR, and so I swapped those out as well.
Again, the taillights are marginally brighter.
Two issues; the marker LED's glow slightly when the car is off and the parking lights/markers are as well. After a few minutes, the LED's ceased glowing, but after starting the car and tinkering with the taillights, upon shutting the car down again, the LED's continued to glow slightly. The car started normally after sitting overnight and didn't exhibit any symptoms of excessive battery drain.
Issue #2 regards the taillights when the brakes are applied with the LED's now installed. Though they function normally, the relay, somewhere buried behind the dashboard, clicks loudly when the brakes are applied. I suspect that the lower voltage draw of the LED's maybe causing this, but would like some feedback and wonder if any of this is harmful to the relay/electrical system in using the LED's.
Any input is appreciated!

 

My 02 xjr has led and hid everywhere possible. Never with any of those problems. I am using led and hid from morimoto.

 

The PO of my XJR installed HID headlights and the little marker lights inside the front headlights also glow for what seems like forever but it’s really probably 3-5 minutes. I’ve been busy fixing all the other more important things on it so I haven’t had time to research why, but I haven’t had any issues with my battery so I think it’s fine.

 

I think all the cheaper led's glow for a while.