COM2005 Delphi random lights

[saskak]

Yeah, wiggling the stalk definitely turns the headlights on. I managed to get the end cap off, but the design is a bit different than anything I've seen in other blog/forum posts.

I am not too sure how to remove the end bit. It looks like a small plastic thing, rather than two bits that one can squeeze to get the next part off. Does anyone know how to get the rest of the stalk apart? It looks like it needs to be turned anticlockwise or clockwise, but there is a bit of resistance and did not get the courage to twist it completely.

End cap,             end cap removed,          internal
           

[jj9]

Great pictures, but without having the part in hand so to speak it's hard to tell how it would come apart.
If I'm viewing it correctly it looks like the two bits that you squeeze together are behind the end circular part?

Is the plastic pin that is in the centre hole of the end circular bit sort of riveted / melted to secure it?

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[saskak]

Great pictures, but without having the part in hand so to speak it's hard to tell how it would come apart.
If I'm viewing it correctly it looks like the two bits that you squeeze together are behind the end circular part?

Is the plastic pin that is in the centre hole of the end circular bit sort of riveted / melted to secure it?

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I know that it is difficult without seeing it, I appreciate any help though.
The very middle thing is not squeezable, it has two holes in the middle, but both holes are off-centre. The one on the left has some sort of pin inside that holds the whole thing (as far as I can see). It does not seem riveted/melted to hold it in place. The very middle thing rotates 1/4 turn on this small pin, I cannot quite see (too small) if the pin rotates as well, so to guess if it is welded/melted with the plastic.  Because the holes are off-centre, the thing cannot be fully rotated.

I guess they have heated the pin (seems metal, although uncertain) and stuck it in, the plastic cools around and stops everything coming apart, but that is a bit of a guess, it might not be like that. Who the hell designs something that cannot be taken apart fairly easy.

[Gryffindor]

I was going to recommend the same vid as jj9, and agree that the problem is most likely due to wear, therefore at some point subject to wear. This probably means either the rotary contacts inside the com unit, or the rotary contacts inside the switch as you suggest with your link to that blog. Much much less likely is a possible wearing cable or connector somewhere else, but I think not.

We all know that the wiper stalks can be dismantled, and since both the wiper stalk and the indicator stalk are integral to the com, then logic suggests that the latter can also be dismantled, as the blog suggests and you are led to believe.

One possible point comes to mind: this is obviously an intermittent electrical connection issue, but although the most likely culprit is a worn physical connector such as the ones in the stalk, this could also be cause by other forms of intermittent electrical contact such as arcing, or water/humidity ingress into an otherwise good contactor assembly. Maybe even a stray fragment of copper or some other conductive material. In short, even if all looks okay, a bit of a clean while you're in there would be wise.

If for example a circular pcb track inside the switch has become partly detached from its mounting or board, even if only slightly and not enough to notice at a glance, then it could be causing the problem simply by being physically closer to other electrical contacts, close enough to allow a very weak electrical contact to bridge them in humid conditions. Yes I am pushing the boat out but sometimes we have to.

The big clue I think is that your issue stopped when you turned the sidelights on. In doing this you rotated the circular contactor inside the switch to a different position, thereby preventing the stray connection. Therefore it probably does relate to one small part of that circular track or its contactors.

The second big clue is that it seems to have fixed itself. Could be that a tiny piece of grit or even dust (or perhaps a fragment of copper from the pcb track) got into the switch contactor and was causing the stray contacts somehow, and with some more switch-twiddling you have managed to clear the offending particle out of the way... to somewhere else inside your switch! So if it hasn't caused any physical damage in its travels, perhaps just a good blow of compressed air or contact cleaner might  be all you need for a long and happy future with your current switch.

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Lastly, just in case it's useful. I am far from sure about this but my (incomplete and painfully slowly ongoing) research on com2000s seems to suggest there were a small number of main generations of the devices, as a separate factor to the multiple part number variations.

They are almost always generically referred to as com2000s (except for the title to your thread, so kudos for that), and many of them are indeed com2000s, but a lot of them are actually com2005s or some other number instead even though they seem to be no different.

I won't bore you with why I suspect this, but I think each generation is identified by its 'family name' and that in turn gives us a clue as to when each generation was released; i.e. com2000s possibly first appeared (with bus networks?) in PSA cars around 2000AD (give or take), com2003s in PSA cars around 2003, and com2005 / com2008 ditto.

I couldn't find any higher com designations so I guess the whole arrangement was substantially revised some time after 2008, perhaps with the intro of the B9 or with the dropping of vanbus, or both.

If this is basically correct, there must be some required difference to warrant such upgrades every few years. Answers on a postcard! It could be a change in how the bus networks and their respective devices are arranged, or perhaps a move to a different controller chip in the com unit, or a need to manage newly introduced model features... etc. You yourself noted the change from ribbons to cables between the 2000s and the 2005s.

So in short if you want to try replacing your headlight switch, it might be wise to keep to com2005s in your case.

[saskak]

Thanks Rasputin for the write up. I figured so. It is some sort of intermittent fault, most likely the switch. Inside there are a few copper contacts that wear out or the printed copper contact has slightly dislodged/separated from the flexible connector and thereby giving contact somewhere else. Most of these are in very close proximity to each other and a small twist and it can give an incoherent command to the COM unit, computer turns headlights on as a safety precaution (at least they thought of that).

I basically have 2.5 options.
1. to purchase a second hand com2005 unit and swap it. There are plenty of exactly the same PSA number as mine, so it should be straight forward swap. Problem with this is that I would not know if that one is faulty or close to fail again. THat reminds me of a thread I posted awhile ago with fading 3-line MFD displays. All the displays I bought were fading and I bought a few...haha, but managed to sort it at the end.

1.5. Try to open it myself and fix the copper contacts with solder on one side and adhesive copper tape on the other. I cannot open it, so that is a bit of problem, at least to see the problem. The adhesive copper tape is probably not strong enough for the upper copper contacts to slide on and it will move eventually and resulting in a similar fault.
2. Pay the person to fix it. That probably would be the most sensible option.

These things really bother me. I bet I will purchase a replacement, the replacement will be faulty and then I will contact the person with the know-how to fix it. Then I can take apart the second-hand replacement to see what is the problem, breaking it in the process, probably. Yeah, I would have lost a few quid in the process, but then again my M59 might develop the same problem and then I should be able to fix it myself. Hahaha, probably not.

[jj9]

I've been in the position you are in with the stalk a lot of times when attempting to repair things, you may have to break parts off the end so you can maybe see how it is held.

It's annoying when they construct items that don't come apart, what was wrong with the other design with the squeezable ends.

Came across these whilst searching for info, could be useful if anyone needs a replacement.


Replacement Stalk


Replacement Ribbons


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[saskak]

I've been in the position you are in with the stalk a lot of times when attempting to repair things, you may have to break parts off the end so you can maybe see how it is held.

It's annoying when they construct items that don't come apart, what was wrong with the other design with the squeezable ends.

Came across these whilst searching for info, could be useful if anyone needs a replacement.


Replacement Stalk


Replacement Ribbons


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The stupid new com2005 delphi thing is not with a ribbon, but with proper wire cables. I guess that is a better design, no chance the ribbon can come out easy and/or break. I have not seen a replacement stalk with the cable, only ribbon ones.
I guess I will have to buy the replacement. £30 pounds for the whole COM2005 and all stalks. I would probably pay £30 just to know how this can come apart, hahaha. I've made worse purchases before.

[Gryffindor]

Maybe the way ahead is not to predict downs and let them stall you but to find the ups in between the downs, if that makes any sense. You remind me a bit of my sister, a Gemini who cannot make decisions because all the available options involve some sort of compromise, therefore none of them are worth taking! Try thinking of losses not as losses bit as gains in a different way.

If you try pulling your own stalk apart, you risk putting your car off the road for a while. If you can get an identical replacement for not too much money, then consider that money not as the purchase price for a dodgy second-hand component, but as an insurance policy, allowing you to explore the switch without risking your own car's roadworthiness, and as an investment in your own education, learning all about the nether bits of indicator switches.

Plus if the one you buy is worn out, then you have a very good candidate for practising your repair skills and knowhow out before subjecting a real live patient to your surgical talents.

Many a Victorian doctor would have died (or killed?) for such an opportunity, and a few grave robbers were hung for providing it. But all it will cost you is the price of a meal, a donation from a broken car, and the chance to make another Youtube teardown video.

Yes, saksak, I fully appreciate that you know how to suck eggs backwards and I can't tell you anything you didn't already know years ago - in fact I stand in awe at the help you have given me - but sometimes a little fresh encouragement might help... new eggs are laid every day.

Cluck cluck!

[saskak]

Yeah, many thanks. That what I was trying to get to, gain some knowledge, perhaps it will help someone else further down the line. I am almost certain that the early B9s or the late M59s are the same design.

I will get a second-hand replacement and report back if I have some further info on this.

[jj9]

Yes it looks like that's the way you will have to go.

Keep up posted & Good luck.

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