[xj40] 94 XJ40 High Mounted Stop Lamp

Hello again,
My high mounted stop lamp is not working. There is no
voltage at the bulb sockets. The JHM1153 CD shows the lamp
relay module above the right wheel well. Actually it shows
2 modules, but there is only one existing. Wire colour at
the lamp assembly is green/black and black. I can’t find
these wires anywhere in the boot.

Does anyone have a clue where the relay may really be?–
vkv884j
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In reply to a message from vkv884j sent Wed 24 Oct 2012:

if the book of lies is correct, it shows a black relay, in the
trunk/boot area, right-hand side of car by aerial.
it also operates trunk/boot release and left headlight flash
(security system).–
The original message included these comments:

Does anyone have a clue where the relay may really be?
vkv884j


XJ40 SOVEREIGN 4.0 1990 (G-REG) SOLENT BLUE
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In reply to a message from vkv884j sent Wed 24 Oct 2012:

According to the circuit diagrams for a '94 model, the high
mounted stop light is powered from Relay Module ‘L’ which is
located behind the carpet trim panel in the front right
corner of the trunk forward of the radio antenna. Relay
Module ‘L’ (DBC10422) has a 20-way black connector. Along
side it should be another Relay Module ‘K’ which has a blue
connector (for the HRW and antenna)

I assume that the Green/black wire from that Relay Module
feeds straight in to the cabin and up to the stop light unit
so you won’t see that in the trunk. However, the Black
ground wire from the stop light unit travels in the reverse
direction out of the cabin through the trunk to a ground
point on the trunk floor immediately below the right rear
Bulb Fail Module on the side of the trunk just forward of
the right rear lamp cluster.–
The original message included these comments:

My high mounted stop lamp is not working. There is no
voltage at the bulb sockets. The JHM1153 CD shows the lamp
relay module above the right wheel well. Actually it shows
2 modules, but there is only one existing. Wire colour at
the lamp assembly is green/black and black. I can’t find
these wires anywhere in the boot.
Does anyone have a clue where the relay may really be?


Bryan N, '91 Sovereign 4.0 L, RHD
Cambridgeshire, United Kingdom
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The HMSL on my '94 would work the first few times the brakes were applied but would then cease working until the car had been shut down for several hours due to dodgy solder joints on the board inside the relay module. Removed the board and touched up the solder joints where the relay (one of four inside the module) is mounted to the board. Worked for a while then intermittent operation recurred. Repeated the process with same result. The third time I had the module out and apart I touched up all the solder joints and knock on wood it has worked properly since. Definitely worth trying.

Mike Stone
1994 XJ6/XJ40
160,XXX miles
Springfield, Missouri USASent via Palm Centro� “Yesterday’s Technology Today”

-----Original Message-----

From: “Bryan N” sophistic@btopenworld.com
Subj: Re: [xj40] 94 XJ40 High Mounted Stop Lamp
Date: Thu Oct 25, 2012 2:50 pm
Size: 1K
To: xj40@jag-lovers.org

In reply to a message from vkv884j sent Wed 24 Oct 2012:

According to the circuit diagrams for a '94 model, the high
mounted stop light is powered from Relay Module ‘L’ which is
located behind the carpet trim panel in the front right
corner of the trunk forward of the radio antenna. Relay
Module ‘L’ (DBC10422) has a 20-way black connector. Along
side it should be another Relay Module ‘K’ which has a blue
connector (for the HRW and antenna)

I assume that the Green/black wire from that Relay Module
feeds straight in to the cabin and up to the stop light unit
so you won’t see that in the trunk. However, the Black
ground wire from the stop light unit travels in the reverse
direction out of the cabin through the trunk to a ground
point on the trunk floor immediately below the right rear
Bulb Fail Module on the side of the trunk just forward of
the right rear lamp cluster.

The original message included these comments:

My high mounted stop lamp is not working. There is no
voltage at the bulb sockets. The JHM1153 CD shows the lamp
relay module above the right wheel well. Actually it shows
2 modules, but there is only one existing. Wire colour at
the lamp assembly is green/black and black. I can’t find
these wires anywhere in the boot.
Does anyone have a clue where the relay may really be?


Bryan N, '91 Sovereign 4.0 L, RHD
Cambridgeshire, United Kingdom
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
–Support Jag-lovers - Donate at http://www.jag-lovers.org/donate04.php

Visit the Jag Lovers homepage at http://www.jag-lovers.org for exciting services and resources including Photo Albums, Event Diary / Calendar, On Line Books and more !

Visit the Jag Lovers homepage at http://www.jag-lovers.org for exciting services and resources including Photo Albums, Event Diary / Calendar, On Line Books and more !

Mike - I have the same issue on my '94 - which module did you reflow and does it still work to this day?

I see it’s DBC10422 …still ok on your car after all these years?

Good ol’relay module L, in the fore end of the boot, right side, near the power aerial.


And yes, touch wood, still working fine. Tip: do NOT use Lucas POD (Prince of Darkness) solder when you touch up the joints! :joy:

1 Like

Hey thanks Mike - and hey - who knows, maybe the trunk release will also work again too …we can but hope!!

cheers

There is a good chance as the relay for that (L2) is adjacent to the relay for the stop light (L1). Fingers crossed!

1 Like

Y’know I wouldn’t even have known the damn high mount stop light wasn’t perfectly fine if the mount hadn’t fallen off the back window - on the way home at night, the car always began with red glow in the back seat if I applied the anchors - but once I got to town the “glow” disappeared …plus no BFM warning …So I guess there’s a silver lining to the bloody housing falling off eh?

Now I just have to figure our what to stick it back on with …

In the spirit of not reinventing the wheel check out this thread:

1 Like

Even though the guy used bathroom caulk and it lasted 10 years, I gotta think that would take quite a while to set up and if some of my other tries don’t work, I might give it a go.

Meanwhile I’m going to leave it “down” for a day or two to see if my reflow job actually fixed the problem …no way to tell if I glue it back up as I won’t be able to see it!

Done the solder job but the weather is rather nasty ATM, gale force winds and heavy rain so not eager to go back out and re-fit it. I already got soaked this morning getting the module off!!

Larry - did you read far enough down the thread to get to this reply:

"I live in Vegas and can understand your fustration with the glues letting go in the heat.

What I have found works great is the gasket maker in a tube called ‘‘The Right Stuff’’ Comes in a 5oz can. Stuff is extremely tacky going on and I have found this to be the
only thing that holds up in the hot hot sun. It’s also the best gasket maker I have ever used, I swear by it. "

There is also the 3M VHB clear tape (Very High Bond) that might do the job to secure the HS

Yes, and it sounded good - except for the 24hr setup time …not sure I can handle that, maybe as a last resort. Gonna try Gorilla first, mainly because I’ve got some handy. If that fails then I might go with the long-setup solution.

Looks like it just might - also noticed GoPro stickums are made with that and I just might have a couple of those lying around …now where did I put them … :face_with_head_bandage:

So thought I’d give the tape a try, couldn’t find the Gopro stickums so bought a roll of VHB on Amazon, will give it a go tomorrow …figured it might come in handy even if it doesn’t hold on the HB light …

I used it to attach my WISH ‘J’ LED’s to the bar on my XJR;

1 Like

Nice! I might to the same thing on the back for additional backup illumination, I’m blind as a bat!

I fitted these to the wifes Mazda as reverse light, really good.

Tape works! (at least for now) …

Just came back from town where I’d parked behind an X300 VDP …noticed his HBL on the shelf too …almost wrote him a note and even thought about hanging around till he got back as I still had the alcohol wipes, scissors and VHB tape sitting on the back seat …almost!