I’ve been using another car since 20th December so I removed the battery from the Jag and fully charged it.
The car has been standing without a battery on my driveway since then.
It was working faultlessly and had been for months prior to this.
I refitted it today and started the car.
The first thing I noticed was the radio/cd/cassette did not ask for the security code when I first turned it on ? This has never happened before, even when the battery has been disconnected for just a few minutes it has always required the code to get it working again. This time I turned it on and it all worked normally without the need for the code. It’s not something I’m too worried about but have mentioned it in case it is linked somehow to the main problem I have.
The side / parking lights will not work. The dash illuminates as normal with the switch in the first position but both front and rear lights are not working. With the switch in the second position the front headlights operate but still no rear lights, although the brake and reversing lights are working. The main beam also works as it should.
I also have another problem with the interior lights flashing like strobe lights accompanied with the sound of a relay clicking away like mad coming from somewhere under the left/passenger side of the dash as soon as a door is opened. This stops as soon as the door is closed, but starts again if any door is opened. I have had this particular problem before in the past but it’s always been very short lived and usually closing the door once or twice would cure it for a few months but now it seems permanent.
Any advice regarding where to look first would be greatly appreciated, particularly regarding the side/ rear lights.
Cheers.
My first thought is that you have a problem with the ‘auxiliary side light relay’ - the one in the green base on the component panel under the passenger side dash. Perhaps a corroded contact? Try removing and then replacing it to see if that clears the problem of the side and tail lights.
Coincidentally the ‘A/C and Radio relay’ in the black base is on that same component panel as is the ‘Interior Light relay’ (yellow base). I wonder if there is a problem with that component panel which is affecting all three oddities you describe?
[You did not mention the year and model of your car!!! - so the info I gave you is for a '90 MY. If your car is not a '90, then the info may be different to that stated]
Hi Bryan,
Now that’s what I call a speedy reply, thanks a million I really appreciate it.
Apologies for not mentioning model and year, I did not realise it wasn’t carried over from the old forum and just assumed it would appear as usual.
It’s a 1993 Jaguarsport XJR 4.0 l. It’s basically an XJ 40 but with some different trim and suspension and engine mods but I’m guessing the electrical system would be standard.
I’ll go in search of that component panel tomorrow when it’s daylight. From what you say, especially the term ’ Auxilliary side light relay ’ I feel almost certain I’ll find something amiss in that area. Do you know if it would be in the same place on my model year.
Cheers.
Casso - methinks you may have an issue with relay module ‘H’ - check out this post from our fount of knowledge, Bryan N.: [xj40] 1994 xj40 relay codes [this is from the old Jag-lovers forum].
Could be a bad cable connection or, as was once the case with my '94 car, dodgy solder joints on the board inside the module.
Well, a '93 model blows my theory - the electrics are quite different to a '90 model.
On a '93, the side and tail lights are controlled by a Relay Module ‘H’ in the yellow base under the passenger side dash. alongside that is Relay Module ‘F’ in a red base which controls the interior lights. It would be most unlikely coincidence that both of those are defective at the same time.
Of course, the side/tail light problem could be as simple as a blown fuse - B2 in the RH fuse box or a bad solder joint in that fuse holder.
Given their physical proximity could it be that both modules have suffered from moisture ingress (fancy way of saying gotten wet), or that the cables to both have been disturbed / damaged?
Is there a quick way I can tell if my car is actually a 93 model ? Just to make finding the bit I need to find easier. It was first registered in mid February of 93, but I read that the xjr modifications were carried out at the TWR site in Rugby. I don’t know how long each car took to complete, but if their was some form of queue I suppose it could easily be a 92 built model ? I know for sure from the heritage site that my engine number is earlier than 93.
Cheers guys.
I believe that the ‘build date’ to which you refer was not shown on UK VIN cars as it appears on the US VIN cars (they being a different VIN sequence)
On Casso’s car, if the last six numerals of the VIN are earlier than ‘667829’ then the car is not a '93 model.
That being the case, the fitment of ‘Relay Modules’ as described in my earlier post does not apply and he can go back to investigating the individual relays on the component panel I described in my original response.
Bryan - I did not know the label was not affixed to other markets’ vehicles as they were to the US vehicles. As you note, the last 6 digits are the key as they are a sequential number for the series of vehicle irrespective of market. Just for grins, try this VIN decoder and see what it shows for model year. It was accurate for my car.
The easy way to determine whether the car is a 1992 model year or a 1993 model year car built in 1992 is whether the battery is in the boot/trunk or under the bonnet/hood. In 1993 model year cars, the battery is in the boot - the 1992 car has its battery fitted in the engine compartment. Another easily spotted difference is in the electric seat controls - the '93MY has the large trapezoidal type in the photo, whereas the 1992 cars have the earlier and more slender rectangular type. The head restraints are different too - with the 1992 models having the earlier sausage roll type at the rear, and built in lights on the front ones.
My own car is a 1993 model year car, built in October 1992 - VIN 672###
As to the problems, the exterior lighting fault does display similar symptoms to my car some years ago (unbelievably its only electrical fault over all these years) - which did turn out to be Relay module ‘H’ part number DBC10009 - the one with the yellow base, just as Bryan n said it would be all those years ago! I replaced it and the fault has not reoccurred.
I have heard of a car which suffered bizarre lighting symptoms on which DBC10009 was not faulty however - that turned out to be a faulty lighting logic module.
The strobe effect on the interior lights could be the door ajar microswitch - these are sided/front&rear so you would need to have the correct one. They are fitted to the door latch and a bit of a job to get to!
The only flaw in this theory of mine is that the strobe starts when any of the doors are opened - rather than just triggered by the door with a faulty microswitch. I find it very unlikely that all of them would fail at the same time, so it could well be another culprit is to blame. The security switch on the centre console panel will lock all the doors - could a fault there cause a strobe light effect?
The example is of a Federal VIN and can further be translated thus:-
1st to 3rd position - SAJ = Jaguar United Kingdom
4th position, Model line - H = XJ6 Sovereign
5th position, Class/Restraint - X = Driver/Passenger Airbag
6th position, Body style - 1 = Four door sedan
7th position, Engine code - 7 = 4.0 litre six cylinder
8th position, Transmission/Steering - 4 = Automatic LHD
9th position, Check digit - 8 = 8
10th position, Model Year - R = 1994
11th position, Assembly plant = C = Browns Lane, England
12th to 17th position, Production Sequence Number = 689540
An Update.
My car is definitely a 93 model. The battery is in the boot and the vin No. begins 677.
I was up with the sparrows this morning and removed both knee bolsters to have a look.
I think I’m getting somewhere now thanks to all the input from you chaps.
I have now determined that it is only the drivers door that triggers the interior light strobe effect and rapid clicking noise.
I’m about 95% convinced it is the black box with the red plug connector and socket that makes the clicking noise.
I’ll investigate the door ajar micro switch tomorrow.
As far as I could see and feel with my hands everywhere looked dry under the dash, with no signs of water leaking in, and the connections to all the boxes etc looked clean and corrosion free but I gave it all a spray with WD40 anyway.
I turned the light switch to pos 2 and to my surprise the rear lights came on but the front ones were still not lit. I stood pondering for about 15 seconds and then the front lights came on ?
I tried switching them on and off several times and they worked first time every time with no delay between front and rear.
I left the knee bolsters off and went for a 15 mile drive with the heater on max and the windows slightly open to give the inside a good airing, stopping every few miles just to try the sidelights. It was still daylight but I’d brought along two small LED torches to illuminate the rear lenses should I lose the rear lights sometime during the journey but they came on as normal when it did begin to go dark on my way home.
I have found a DBC 10009 relay module available so I will be ordering it tonight so I can change it and then investigate inside the original without my car being off the road.
I’d like to replace the red one too, I’m thinking all that rapid clicking can’t have been good for it even though it’s most likely caused by the door switch which I’ll also be ordering.
Does anyone know what part number the red box is ?
Thanks again Bryan, Mike and David for the invaluable help and overall confidence boost.
I could not run my car without you guys, and other forum members behind me.
cheers.
Casso - sounds like progress! It is relatively easy to remove the relay modules (like the DBC 10009 you have ordered), they just snap onto the mounting rails. Carefully remove the cover by using a thin-bladed screwdriver to lift the tabs and the circuit board slides out. Look for cold or broken solder joints or you can do as I did and just go ahead and reflow them. I started with the ones where the relays mount to the board, then reconnected and tested it. When I had an issue with the relay module in the boot that controls the high-mounted stop (center brake) light it took a couple of tries reflowing the joints but that did the trick, and has held up for better than five years. By the way, with the cover off the connected module you can manually work the relays if needed for troubleshooting purposes.
It may also be the lighting logic module - exactly what is affected by DBC10009 will be in the Jag-Lover’s archive on the old site somewhere. IIRC, Bryan N posted up a list of symptoms and their combinations at some point - about 2008, IIRC. If you put in DBC10009 to the search engine there and limit the posts to ‘Bryan N’ (it’s what I often do to reduce the number of hits and to prevent drowning in knowledge) then something will come up.
On my car it was the rear lights which were reluctant to come on, together with radio problems and the cigar lighter not working. These relay modules have quite a diverse array of functions, so a failure in one can manifest a strange array of seemingly disconnected faults.
A failing lighting logic module can also cause strange behaviour and failures in the lights. IIRC the part number for this is JLM11354. It is worth finding the list of functions covered by DBC10009 to determine whether the fault lies there or in the lighting logic module. That said, DBC10009 seems to be MUCH more failure prone than the other modules which are extremely reliable and rarely fail, so it is actually a part which is well worth having as a spare even if it is not the cause of the problem. I have a spare one just in case! I wonder why it is so much more likely to fail? - Maybe there is something in the circuit designs which stress it?
David.
It’s poured with rain all day here so I have not had chance to investigate the door ajar switch yet.
I tried your suggestion to search for Bryan’s post regarding the DBC10009 box, but when I try to access anything on the old site I just get directed straight back here ? I click old site at the top, then click search, then I’m back here ! I’m such a slow learner with PC stuff. I’d only just mastered the old site after years being a member and then they go and change it all.
I’m not griping, it’s like having a new car, it’s just a case of getting used to it. I’ll get the hang of all eventually, and I can see the improvements and benefits already, it’s me that’s slow, not the new site having problems !!
I have solved quite a few problems in the past thanks to searches, and most often Bryan’s responses to other members with problems… I’m quite comfortable with a spanner in my hand, but the electrical system is virtually a mystery to me. I can use a test meter proficiently and solder to a decent standard, but I struggle to understand the wiring diagrams in the manuals I have, and also find that now I have to use a magnifying glass to see them properly ! I find It’s not only much easier to read, but also to understand Bryan explaining it all to somebody else !
It was your mentioning of the cigar lighter not working that has raised my hopes of the fault definitely being within the H control box. My kids bought me one of those dash cam recorders for Christmas and when I pushed the lighter into the socket to test it beforehand, it was dead. We tried again later and the lighter popped out cherry red as expected and the camera powered up fine, so it seems I also have an intermittent fault with that too, and hopefully it’s further evidence that the soon to arrive replacement H box will cure it all.
Your last line had me thinking, as I’ve already mentioned I know little about the electrics on our cars, but could it be possible that using the cigar lighter socket for far longer periods than it was intended for when it was designed, is damaging the H box ? A device that was meant to operate for 15 seconds every few hours or so, is now charging mobile phones and running other devices for much longer periods, maybe they overheat ? Just a thought.
Thanks for the info on the lighting module. No surprise it’s N/A on the JDHT site but I have a few good sources for spares and if I do eventually need one, it’s a lot easier having the part number, and also knowing what it actually looks like helps too !
I treated myself to a new fine point solder iron and solder today in preparation for a bit of joint flowing. I’ll see if I can take any worthwhile pictures of anything I find inside the old box, but I also intend opening up the used replacement before installing and checking it all over for dry joints with a powerful eye loop. Anything remotely suspicious will see the new iron in use first.
Cheers.
Casso - no need to go to the old site to search, you can search from the new site. You should see a magnifying glass just left of your ‘avatar’ (in your case a ‘C’ within a solid circle) near the top of this page. Click on that magnifier and search away.
---- White/red ------ Ignition switched power from Ignition ‘ON’ relay
[To relay H4 (switching only) via Fuse 6, Centre fuse box when key at (II)]
---- Red/brown – Battery power to rear cigar lighter
[From relay H4]
---- Brown/white – Battery power to hood lights and cigar lighter lamps
[From relay H2]
---- Brown/black – Battery power from Fuse C2, Left fuse box
[To relay H2 (power + switching)]
---- not used
---- Blue/black ---- To side light switch
[From relay H3]
---- Blue/green — From side & tail light relays in BFMs and glove box lamps
[Common to relays H2 and H3 - goes to ground when relay H3 is energised to
illuminate side & tail lamps and to energise relay H2 – see 3 above]
---- not used
---- Brown/yellow – Battery power from Fuse B2, Right fuse box
[Common to relays H1 (power +switching) and H3 (switching only)]
---- Light green/orange --Ignition switched power to major systems
[From relay H1]
[Radio, Blowers, Telephone, Power Seats and Mirrors, Security ECU]
---- Brown/green – Battery power from Fuse C1, Right fuse box
[To relay H4 (power only)]
---- Orange/brown – Battery power to front cigar lighter
[From relay H4]
---- Black ----Permanent ground at earth stud in centre console behind ‘J’ gate
[From relay H4]
Thanks Mike for pointing out how to use the search archives. It was definitely a ’ Doh’ moment when I found how easy it was.
Bryan, Thanks for taking the trouble to retrieve and re-post your original post. If it turns out the H box is not at fault that info is going to be invaluable.
Cheers.
Hi Everyone,
The replacement ‘H’ control box finally arrived on Friday. I opened it up to look inside before fitting it, and I’m so glad I did. There are four little relay/contact devices soldered in place on the board, the two in the middle had pins that had become entirely detached from the board. The solder had cracked all the way around the joints.
I re-soldered just about every joint in there and tested it on the cat today. Up to now it seems to have cured all the problems I had. The sidelights are working properly and so is the cigar lighter. Also the strobe effect from the interior lights has disappeared too. I also used to have an annoying clicking noise coming from that area even when driving in daylight with no lights on. I used to hear it clicking randomly when I’d be sitting at traffic lights and always wondered what it might be, that also seems to have disappeared too.
I opened the original ‘H’ box and that was EXACTLY the same inside with the same two pins loose and not making a connection on the board. The only difference is this old board also has a brown sticky sort of crystal like substance that has formed around quite a few of the soldered points, I have no idea what it is but I’ll get some electrical cleaner and clean it all before I re-solder it all up to keep as a spare.
I always get so stressed whenever my car has an electrical issue, and I am such a pessimist I always think it is going to be something much more of a problem than it usually turns out to be. Probably down to my fear of the cars electrical system and the trouble I have in understanding the diagrams. !4 years of XJ40 ownership should have taught me by now that it’s never as bad as I first thought.
Anyway, I’m a very happy owner again, so thanks Bryan, Mike and David for all your help and input, I wouldn’t have had a chance without you guys.
Cheers.
