406 2.1td - Engine shuts off during driving, then can be started normal

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white exec
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Re: 406 2.1td - Engine shuts off during driving, then can be started normal

Post by white exec »

Have seen that, too.
Try driving with just the lone key in the IGN, nothing else attached.

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Re: 406 2.1td - Engine shuts off during driving, then can be started normal

Post by joydivision »

Yes, sure, what you're saying makes perfect sense and is very well possible. But it still shows that the ignition switch (or/and barrel) is worn, as it shouldn't do this under normal circumstances... So , I'd rather fix it, than going around with a single key and my key bunch, that would be a serious risk of loosing the key for the car...

I'm glad I took the covers off... did it today and was easy. It's in fact the other one that exists. The key barrel is 447022. Here are some photos (not so good... hard to take...) I took of it and also a couple of images off the net. Now I know how to find the right one and order. I think it won't be very easy to fit, though, because the cables are all very tightly packed together and access is difficult, I also remember reading in Haynes manual about some "locking pin", but I'll research well and maybe there's even some video on Youtube, you never know. It also helps that I found pics on the net of the whole thing dismantled, helps to understand how it goes all together. Most of them are the complete unit. One of them shows only the ignition switch itself.
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Images from the net:
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white exec
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Re: 406 2.1td - Engine shuts off during driving, then can be started normal

Post by white exec »

The suggestion of just a single key was just to help diagnose the problem, rather than a fix.
Intermittent contacts in the electrical part of the switch are quite common, with age.

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Re: 406 2.1td - Engine shuts off during driving, then can be started normal

Post by joydivision »

Yes, sure :)
The thing is: hasn't done it for three days of daily use of the car... and this with the whole key bunch... so if I'd use a single key, I couldn't be sure that the problem is gone or not, unless doing this during, I don't know, maybe a month... and I'd rather have the problems of the car solved asap. I just found one used ignition barrel with ignition switch for sale on the net here from PT which is not expensive and looks quite well, not worn, so I will order it.

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Re: 406 2.1td - Engine shuts off during driving, then can be started normal

Post by moizeau »

Have you got a Haynes BOL's? If not I can scan the relevant page.

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Re: 406 2.1td - Engine shuts off during driving, then can be started normal

Post by Pablo »

When driving turn off ignition and see if the same circumstances are replicated i.e. fuel gauge and ign light, or whether it shows up differently. This should either confirm or eliminate the switch. It could still be a break in the circuit somewhere else though.

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Re: 406 2.1td - Engine shuts off during driving, then can be started normal

Post by white exec »

Be really careful doing that, as there is a risk that the steering lock could engage. :!:
Probably best done on a non-public and deserted road.

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Re: 406 2.1td - Engine shuts off during driving, then can be started normal

Post by joydivision »

moizeau: yes, I've got the Haynes Fantasy Guidance Book :D

Pablo: yes, I did this with the car parked, it's not that precise but quite similar, and yes, the result was similar, but as the keys is turned correctly, the light only goes on briefly. I suppose that the bad contact in the ignition switch makes it go to that "intermediate" position which shouldn't even exist and that is between the "engine on" and "accessories" positions... otherwise it would go to ignition on position (with the lights all on), which is what happens if I make the engine stall.

Chris: thanks for the warning, yes, that could be dangerous indeed.

I already ordered a used key barrel with ignition switch that I found online here in PT for a very low price and appears to be in very good condition.
Now, there are a couple of things I'm not sure I understand well: this comes complete with keys and everything - if the barrel happens to be in much better shape than mine (which seems very worn), can I exchange it? This would mean that I'd have to use the old key for opening the doors and the "new" for ignition? Wouldn't that raise a problem with the transponder security thing? I mean, that black chip that's contained inside the key fob. Or does the car have the ability to synchronize to more than one key at a time? This makes me remember that I tried to resynchronize with the existing key (as the remote control is not working, although I'm positive I might have repaired it, at least red light goes on), following instructions found on the internet, but the car didn't reply to this (no beeps) and the remote didn't start working, Could this mean there's a problem with the electronics responsible for this and could this make the use of a different key barrel and key impossible? I don't want to end up having to take the key barrel out again because the car doesn't start anymore...
If there's any risk of this happening, I will only substitute the ignition switch, not the key barrel.

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Re: 406 2.1td - Engine shuts off during driving, then can be started normal

Post by joydivision »

So, I just replaced the ignition switch. While unmounting, I discovered that someone had butchered the locking clip, possibly when the contacts for the blower motor were destroyed: probably they didn't know about the fact that key has to be put into position 1 to be able to release the clip. Incredible. So, they had just broken off the clip at its base, then probably managed somehow to press them out from the top, I don't know, and later fit in back the remains so that barrel wouldn't fall out. It meant that I had to unmount the whole barrel/ignitions switch assembly from the steering column (fortunately easy, just two hex screws) and spent a good half an hour with trying to remove the two remains of the clip, finally I managed to do it. I then unmounted the ignition switch from the barrel I bought (decided not to change the barrel - although it is in better shape, key springs well into positions, because I didn't want the trouble with the two different keys and all) and mounted it into the existing barrel, attaching the "new" clip and also the wiring retention clip (they hadn't fitted it - it simply wasn't there). Assembled it all back together and works fine. I now think that the problem would have been caused by a combination of two things: the barrel being worn, which means I have in fact to be careful as a lot of keys on the key bunch or my knee might turn the key slightly back, which could switch ignition off. But the other factor would surely have been the ignition switch itself, not only because it was probably worn, but also because they didn't mount the wiring retention and the locking clip was broken, so the whole thing was kind of loose.
So I hope it will be fine now, even without changing the barrel. Let's see.
Btw, interesting side note: the used ignition switch I bought, although looking good and measuring well (and working well for me) has a tiny problem, guess what? those damn blower motor contacts are gone... They really made a design fault with this, no matter usually has to be fixed in the vast majority of Peugeot and Citroen which used this method from that time. For me it's no problem, as here it has already been fixed, being the blower powered by a different wire.

Here's how it looked like when I got to it: no wiring retention and locking clip broken into two bits which were stuck in there. Second photo shows them out, after hard work...
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So, hopefully this problem is fixed now. Is it possible to modify titles of threads in this forum to add "SOLVED" or something or is this not a good practice? Clearly I will have to wait a few weeks to make sure the problem is really gone (it was so rare already). Thanks for all the help.

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white exec
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Re: 406 2.1td - Engine shuts off during driving, then can be started normal

Post by white exec »

Well done in seeing that repair through! Persistence pays off!
As you say, a long-standing defect with design, leaving IGN switch contacts to handle all sorts of high-current loads, including blower, and the starter solenoid.
As well as repairs/replacements, a good few owners have added additional relays to cope with these heavy load items, and this sorts the problem completely.
Citroen did the same thing on some models with headlights - for some reason providing a relay for dipped beam, but not for main - putting extra strain on the lighting stalk/switch.
Bean-counters at work...

The occasional drop of oil on the key (or down the barrel) will help keep the lock innards working.

Sorted? Yes, you can just edit your last post, by changing the title of that post.

joydivision
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Re: 406 2.1td - Engine shuts off during driving, then can be started normal

Post by joydivision »

Yeah, it's tough when they decide to economize a few cents somewhere which later translate into hundreds of euros of repairs for the owner...

Ok, thanks, I will edit this threads title in a few weeks, once I'm sure it's fixed indeed (and if I remember :)