What is with the trunk lights on my 2000 XK8! They always come on when I open the trunk in broad daylight and never come on when I'm in the garage or in my dark driveway.

Tonight I had the car locked and the trunk open (planning work on the convertable top pressure reduction kit install) and noted that, as usual and when I need them, the courtesy lights weren't being courteous.

All of a sudden the beep-beep-beep countdown started and the trunk lights came on. I tapped the fob to stop the countdown and they stayed on. I shut the trunk, opened it, and they were off and stayed that way. No idea why the alarm started.

The lights must be wired into the daylight sensor, that's logical. And maybe connected to the lock system somehow? To the alarm, too? I haven't found a pattern yet.

This has to be the smallest problem on the forum, I'm a lucky guy!

 

I'm going to watch this thread... I have a similar issue with my '99 XJR. The main difference with mine is that it appears to be random not really associated with daylight or otherwise. I thought it had to do with how quickly I opened the trunk after pressing the release, but that hasn't proven true either. My guess is that it has something to do with the mercury switch.

 

I had an intermittent problem with the trunks lights, would seem to come on during the day and not at night! Eventually they came on when they pleased.
Turned out to be the microswitch by the lid lock. No light sensor interaction!
Replaced it with a tilt switch.
Lights behave themselves now.

 

Remember that the BPM will shut down any light that is left on more than 20 minutes when the key switch is off to save the battery. Could be an issue with the BPM.

 

Not sure what you have going on but it could be a case of the Gremlins! My interior light at times will turn on and then dim out and thought it was a case of bad grounds. I never got around to check them. I do recall a time when I unlatched the trunk with the remote and the security system was on like yours and my alarm went off; however, I thought it was because I closed the lid just enough to make the lights blink and I thought that was the cause. I have opened the trunk the same way many times since but was aware of I was doing and making every effort not to allow the trunk lid to close until I was ready. As for the lights working when they want I would check the switch at the trunk.

Electrical http://www.gusglikas.com/AutoRepairElectrical.htm

 

i'll guess the microswitch in the trunk also...i'm with Dan.

 

I just chased this down in mine as well. I do have a bad microswitch. From the size of that microswitch I cannot beleive it can handle the current of the two lamps. I bet that is why they are so troublesome.

I removed mine from the latch and connected it to my ohmmeter. when actuating it I get resistance readings from 2000 ohms to about 200 ohms. That's probably why the lights randomly work for some people. Sometimes the switch provides enough of a current path to light the lamps, and sometimes it doesn't.

The switch also looks it would be $30+ for a $2 part. I guess I need to do some research again...

 

Take the micro switch to an electronics parts supply and see if they can match it. Maybe even online search.

 

I think your Jag is just Effing with your mind!

 

I found it. It is a "custom" version of a Cherry DK series sealed snap switch.

It's rated at a maximum of 2 Amps, A good engineer wouldn't use it to switch more than half it's rating, or 1 Amp. I'm not sure that the two trunk lamp ratings are.

Anyway, I haven't found a supplier yet for these DK switches. Maybe they are available as part of another latch somewhere...

http://www.cherrycorp.com/english/sw.../sealed/dk.htm

 

If you find a supplier for this Cherry microswitch please post it.
I ended up using a tilt switch.

 

I've just run up to the same need. Did you ever find a supplier for these DK switches?

 

May I join this group of the trunk-light oppressed? I'm going nuts with my lights not coming on at all - never. I'm completely perplexed even though I've 3 official wiring diagrams (only one shows my wire colors, and it's only partially correct at that).

I shorted the harness lines at the connector to the switch's pigtail and the lights come on. A short across the switch's lugs also turns the lights on. Since the switch is normally closed (i.e., depression of switch's accuator by trunk latch turns lights off), lights should come on with switch in normal position, but don't. Conclusion is switch is bad, but it shows good continuity and about 5 ohms so it should be okay (?). What's going on ??
I reviewed the Cherry website and agree our switch is a Cherry DK but all the actuators differ from mine (mine has a black plastic wedge on the end). The local Cherry switch distributor (San Jose, Calif) reported actuator was probably a Jaguar proprietary add that's no longer, if ever, available from Cherry but he'll check whether it can be removed/reinstalled onto other units. Otherwise, switches are available.

Anyone have any further ideas about the optimal resolution for this globally critical issue?

 

I've no news from the Cherry switch distributor, so I went to the junk yard and found a good one (i.e., low mileage car with front damage). Plugged it in and it worked the first time switch's plunger was depressed. From second attempt on, nothing happens. No lights!!!!! Possible that line voltage is burning the little guy out?

 

Man, that would be frustrating! Check make sure you didn't blow a fuse with the working switch. Can you 'test' the switches?

 

yep. as in the earlier post, the new switch has perfect continuity and shows few ohms. Me thinks maybe the diode shown in the wiring diagrams is acting up. Who knows, it's a Jag. No wonder cats have 9 lives - there're many frustrated owners.

 

Add me to the list of people having trouble with the trunk lights. Mine seem to follow the rule of not turning on when the trunk is lifted, but if the trunk is left open they turn on after about a minute or two.

 

I had this problem also when I first bought my 1999 " 8 ", they just would not come on. I worked the plunger/switch and it made no difference. While I was messing around with the security module in the boot/trunk I was using some WD40 so the switch was sprayed and the fluid worked into the unit, may take a few applications for different conditions. The lights came on and worked as normal after that.
This is just my own personal experience reported as it happened for my car.
Hope it is of use to someone.
Good luck,

ArtyH

 

Andy,

Thanks. Your insight sounds pretty logical.

Sometimes I've been known to ask. Why is it that SOME Jag parts are seemingly SO inferior? Like the 'cup holders'? OMG When I first saw these I thought, You've got to be kidding?!

Sounds like the trunk courtesy lights could have been designed a bit better pretty easily.

But then, what do I know?

Happily I don't have complaints per se, just saying...

Sandy

 

I too have the trunk lighting blues...stumbled upon this source for the micro switch:

LNC6242AC

jagbits dot com part number LNC6242AC for trunk lights and trunk ajar warning