some hours ago my central door lock switch has come apart for no obvious reason - I opened the doors for the passengers when entering the car and at the end of the ride the upper black plastic part was sitting loosely on top of the switch. Though I wasn’t really able to check in the dark the part seems to be broken.
Is this a well-known failure mode (and I don’t mean “plastic brittle from age? Well, sure …” and, if so, is there any procedure to restore function? If I have to bite the bullet and replace, can I look out for SIII parts? The part # indicated for SII cars is DAC.1301 (C.40126) and the same as the six power window switches. The SNG parts book lists DAC.2747 (DAC.1320) for SIII cars, but they look pretty much identical, except for what looks like different position of spade connectors.
Could anyone please confirm that SIII are/are not interchangeable?
Are you talking about the black rocker switch on the console?
My car is an SIII and may be different. I thought mine disabled the windows and sun roof when open. And that paddles up front circa the A pillar did the door locking.
Look at the part of your switch that came adrift. It “should” have two small posts on each side.
Those ride in holes in the side of the switch and form the fulcrum on which it rocks. I suspect one or both have just worn away or broke.
With your well known ingenuity, I suspect you can make replacements of a better material and drill the rocker to house them. good for another 30 + and more…
indeed, SIII cars differ from SII cars in that technical progress provided them with “power locks” instead of “central locking” … To be more precise: In SIII cars the driver’s (maybe also the passenger’s?) door lock triggers all other locks, whereas in SII cars the door locks are not operating units. Instead you have to open the lock, get in the car and “centrally” unlock all other door locks via a rocker switch mounted on the flat part of the central console. I’m not very familiar with SIII cars, but I think Jaguar made use of this switch - or rather its position in the console - for the sunroof.
In the daylight I saw that the plastic pivot of the rocker part of the switch had broken off, just like you were assuming. It doesn’t look like a good spot for glueing and there is not much space for fixing new pins securely either. For some moments I thought of installing a James Bond Aston Martin metal toggle switch and add signs like “armed” and “unarmed”, but I guess I’ll keep it simple and get an original replacement switch.
Yet, the question remains, as this rocker switch on SII cars is identical to the power windows switches and thereby begs the question whether the power windows switches of SIII cars interchange.
Not sure I understand the question, Jochen. The power window switches on S3 cars interchange among themselves, but the window switches are different among all three series of XJ cars. The S3 switches are quite a bit smaller than S2, and they have pins for connection which require special multi-wire connectors. I suspect that they are different electrically as well. Some window motors have two windings with a common ground (S1), while others have permanent magnets and reverse rotation via reversing the polarity to a single winding (maybe S2 and/or S3; not sure). There are also various lock-out schemes that allow the console mounted window switches to override those accessible to the rear seat passengers.
I don 't recall the Bond arming switch. But, I’m guessing it was derived from aircraft switched. DPT with a guard over the toggle to prevent accidental engagement. Many found their way into racing. Great quality and as post WWII surplus a bargain. I’ve used them.
Bob’s electrical comparison is far better than I could do.
My idea of a repair was in the mechanical function.
I agree, even Gorilla Glue might not be good enough. Got some on my desk to seek to affix the ear piece to the hinge on my spare spec’s.
Rough idea: Smoothen the spot where the fulcrum pin was. Drill a hole in that place, all the way or at least most of the way across. The size of the hole just a bit larger than the “new” fulcrum pin of a better material. Glue it in place.
The long way around? No doubt. Just fits my “fix” mode.
When I removed the grill in front of the wind screen on my car to clean it up. I found it missing a pin that secured it in place. The thing looked awful. Peeling faked chrome revealing bilious yellow plastic. I drilled a little hole. Screwed in small screw. Cut off the head. Better than “factory”.
Indeed, Carl! I used to use a lot of WWII surplus stuff as well. Do you remember the toggle switches that had a round white bead at the tip that glowed in the dark? Lots of Radium, I’ll bet. But even back in the fifties, the military surplus stuff looked old-fashioned and obsolete to me. I loved the British car black plastic toggle switches, for example. Still do.
I’ve an old clock in a box. Interesting box and “works: The hands on the clock are dark !! But, if I shine a flash light " torch” on the hands, they glow green for a bit.
your information, Bob, was exactly what I needed! I’m still having trouble understanding why Jaguar changed the power windows switches from Lucas 178 SA
to Lucas 152 SA
as the window motors don’t seem to have been changed, but if the connectors are different, I’ll get myself the correct switch … At prices around 30 EUR I’m little tempted to pour in one whole valuable Saturday afternoon.
Many years ago, though, my Spitfire fell victim to car thieves. They would cut the soft top, get in the car and break off the plastic steering column cover to get access to the ignition wires. In that course they broke off the red plastic hazard switch. Fortunately, their attempt failed as there was no battery in the car, but in those days a hazard switch cost well over 120 DM and I already had a hard time paying for a new soft top. So I became inventive, had an internal thread cut into a piece of aluminum tube, cut it to a suitable length, filled the top part with red transparent resin and covered all in transparent coat. It looked better than the original, still exists today, but has made way to an original part I found on a wrecker’s yard in New Zealand.
BTW, this is what the original Aston DB5 centre (with “re”) console looked like
Maybe, I should think about it once more, though. After all, the original owner of my car was working for MI6 during WWII and inventing edible paper and invisible ink for the British spies. I like the idea that he may have been in the team that inspired Ian Fleming to create Q … For whatever that would mean, I have yet to find those machine guns!
tonight I had the chance to pull the switch. You have to first prise out the slope part, then unscrew the two screws front and the one screw at the front trailing edge of the cubby box. Then you can press in the four tabs (clearly visible in the first picture) and push the switch forward.
Failure analysis showed that Carl was right: Both protrusions of the rocker part forming the axle of the rocker had broken off. One had fallen into the housing, one was still dangling about. The first picture shows the round holes in the housing in which the axle stubs are placed.
The rest of the switch seems ok, albeit pretty dirty. I’ll give it a try, clean it up and try to make up a new axle. Should be a lot less than a whole afternoon. In fact, there is a second layer of plastic behind those tabs that have broken off. It should be easy to drill a hole and find a thick nail or 2 mm bolt cut to length.
The innards of the switch still escape me: There is a coil spring, a white plastic retainer and a brass roller. I take it they are meant to sit inside the rocker part providing for release pressure. Yet, I can’t see the purpose of the brass part, as there is no contact to be made and the roller thing can’t possibly change the rocking operation.
Finally, I totally failed in restoring function by transplanting one of the working window switches. I installed one twice, am pretty sure I got all the connectors right, but absolutely nothing would happen. Hmmm, now that I think of it: Could I have blown a fuse by shorting something with the broken switch? Questions over questions - I’ll get to it on Sunday, hopefully …
When seeking mechanical or electrical logic in things, I find that getting into a cool, calm and collected mode and just staring at the subject often works.
As to that switch, I suspect it reverses voltage flow.
Or merely throw volts one in one posaition and the other way in the other. DPDT! A common and two loads,
The roller and plate have to do with the mechanical “feel” of the switch, or so I suspect from afar.
though it has become somewhat late tonight I’d like to report back on the switch saga. During the last days I tried to sort out how the innards of the switch belong together and how they function. First let me show you some pics showing everything you always wanted to know about DAC.1301 (Lucas 178 SA), but never dared to ask:
Without any other hint I figured out that the brass roller belonged into the white plastic thing, the coils spring into the central section of the rocker and the white thing on top.
Next thing was the broken tabs: On one of the pictures you see one broken axle tab lying next to the rocker; the other one was dangling about. I removed the sad remainders and drilled a 4mm hole through the central section of the rocker. I found a bamboo satay stick exactly fitting through the holes of the outer switch part. I cleaned up everything, put some silicon oil onto and fitted everything back for a test run.
The functioning of the electrical part was harder to figure out as there are at least six contact points inside the switch: On the first picture above you can see that the rocker part is asymmetrical. The larger side part is obviously made to make contact between the outer contact pairs of the switch - either left or right. If you look at the second picture you can see six rivet heads. They belong to the spade connectors on the reverse that are numbered as you see on the next picture.
The thing that really got me thinking was that the central part of the rocker permanently connects pins 2/3 and 4/5. Fortunately, I found an explanation in my wiring pattern pointing in the same direction:
For the moment the only explanation I can think of is that Lucas may have used different rocker parts to produce a variety of switch signals from the same body, but obviously not needed in SA 178,
So I put everything back together - the satay sticks work a charm; I’m wondering whether they will last for the next 40 years - and tested it: If I put voltage on 4 I have no continuity to 1 or 6 in neutral, but either to 1 or 6 when switching. There is permanent continuity from 2/3 and 4/5. So this thing seems to be fixed. Now let’s see what installation of the switch may bring … But this is for another day.
Hope it works, Jochen. I think these switches are mechanically configurable into several electrical types. It’s basically a switch of the type "double pole, double throw"or DPDT (in English of course). Here, two of the contacts (leftmost among each set of three in your diagram) isn’t brought out, but rather it is connected to the opposite contact on the other pole of the switch. In generic DPDT switches, this wiring is often done externally, creating an “X” on the back of the switch, made up of two wires. The most common application of this setup is polarity reversal. If +12 and earth are applied to 3 and 5, respectively, and a motor or other load connected to 1 and 6, then the load will be energized with one polarity or the opposite, depending on which way the switch is thrown. Centre position is off. In other configurations (without the internal connections or with different ones) other functions would be possible, like three speeds for a fan. The same switch can also be made to be momentary in one position only or in none–two or three stable positions. IMHO.
Congratulations. You bested the beast. I suspect it is better than ever. Bamboo is an incredibly tough material. It should best plastic and be there for as long as you need it and beyond. Ie, a very long time.
And, the presentation will be a great tutorial in the archives.
Is a Satay stick, the same as a swizzle stick?
Oddly considering that it’s natural shape is a tube, it is a desirable floor material!!!
I watched a craft show Saturday. “The Craftsman’s
legacy”. The host is a former “white collar guy” that evolved into a maker of custom motorcycles. And now in TV, visiting and participating in the artistry and craft of others. This show was on making custom bamboo casting rods. Yup, a stick of bamboo was oft used as a fishing pole. Huge difference to a casting rod. Here, the sterms are split several times, to get flats. Those in turn are glued together to form a beam. And then turned to make a very flexible rod. Super slick. And clearly as a laminate, very strong.
Bob:
Yes, DPDT. I have a couple in my shop. Larger than this example. for 120 V. Indeed, the X shaped wires across the back. Intrention: Use on my Atlas lathe. I do use one, but as a simple switch, not in a reversal role. E Bay sourced. New. Very high quality.
To be very brief now: The switch is back in and works a charm - first try, first reaffirming “thunk”!
You know how good it feels when you’ve solved a problem - everything fixed, zero costs and on the losing side only one retaining tab broken off a switch that was already broken and a very slightly indented metal finisher - when I tried to press in said retaining tab …
So, now that I know how the central locking is wired I’ll turn to that remote control.
forgot to reply to your comments on the bamboo: Indeed, bamboo is formidable: Not only do Asian constructors use bamboo scaffolds to erect impressive buildings and specialists make bamboo bicycle frames. It is also a fantastic floor material - we have it in our living room and in our bedroom: It is very hard, has a high content of oil making it very durable even without a clear coat seal and, of course, growing it is fast and much less intrusive to nature than cutting wood in the rain forest or grow monocultures at home.
I was referring to a satay stick for lack of a better term known to me. Just found out that I meant “skewer”. “Satay” is an indonesian dish https://en.wikipedia.org/wiki/Satay typically served on such skewers. What is a swizzle stick?
Compulsory Jag content: I was happy to have found these bamboo sticks, as they permitted a good press fit into the original openings of the switch housing. Using metal bolts I would either have risked to burst the plastic housing or have had to glue in place. For the time being I’m quite satisfied, have used the car today and exercised the central locking several times with great pleasure.
A plastic stick found in fancier bars to stir a concocted mixed drink. Swizzle.
Shish ke bobs. A metal rod with a handle. thread on bits of assorted veggie and meat chunks. On to an oiled grill to cook. I was not aware of their origin.
Carl
and, if so, is there any procedure to restore function? If I have to bite the bullet and replace, can I look out for SIII parts? The part # indicated for SII cars is DAC.1301 (C.40126) and the same as the six power window switches. The SNG parts book lists DAC.2747 (DAC.1320) for SIII cars, but they look pretty much identical, except for what looks like different position of spade connectors.
) console looked like
