406 speedo intermittent reading

ianb · Post by **ianb** » 04 Apr 2003, 20:35

Hello all, my first posting so I hope you can help,
The speedo on my '96 (108k) 406 sometimes stops giving a reading, it'll drop to zero for a few seconds then return to normal reading, this may happen several times in a 30 mile commute when travelling at a steady speed, then not at all for a week or so. It doesn't seem to be related to any specific rev range or road speed... it's driving me nuts.
Any ideas gratefully received.
Thanks

VisaGTi16v · Post by **VisaGTi16v** » 04 Apr 2003, 22:34

Im not sure if the 406 is a cable all the way from the dash to the gearbox or electronic. It could be a number of things like its coming loose from its socket etc or a split in it if its like the old Visa gti ones that were half electronic.
Do you have a Haynes manual as that might show it? if not hopefully somoene else will answer here who has one. If its just the cable thats fauly they are normally under £50 and just a case of threading theading them through the bulkhead etc after taking the binnacles out so not that long a job. Hour, 2 at the most if you took it to a garage. I sersiuosly doubt its the dial itself although that is a possibilitly I guess.
regards
Darren

ianb · Post by **ianb** » 05 Apr 2003, 02:30

I've had a look at the Haynes manual, it's a 3 spanner rating which makes me nervous straight away ...
Haynes says >According to model either a standard cable or transducer unit is fitted, I'll have a proper look on the car tomorrow morning and see if it looks like the pictures.

RussD · Post by **RussD** » 08 Apr 2003, 17:12

Is this a Sagem speedo and do you notice it happening more in hot weather? If so, I may have the answer but you'll have to take the instrument binnacle out!
Russ

ianb · Post by **ianb** » 09 Apr 2003, 18:45

Russ,
No it's a Jaeger, it 's happened sporadically for about a year now so I don't think it's hot weather related, I took the instrument panel off last week to replace a blown bulb so I can deal with that again,
Is your idea specific to the Sagem speedo or could it apply to either type?
thanks

RussD · Post by **RussD** » 10 Apr 2003, 03:40

Hi Ian
I had three problems with my Sagem instruments but I've no idea whether the Jaeger ones suffer from the same problem. Anyway, here's the story....
First the rev counter froze at about 2K revs when the ignition was on (dropped to zero with the ignition off, so it wasn't a stuck mechanism).
Next the speedo kept dropping to zero mph in hot weather.
Finally, the whole instrument pod went dead (except for the backlighting, I think).
If you take the Sagem instrument pod out you'll see that it's made of two main circuit boards - one rigid and one flexible. The join between the boards is formed by a fold in the flexible one over the rigid one that's held in place by a metal clip. ALL the problems described above were caused by one or more of the contacts between the circuit boards not making properly. I cleaned the contacts with meths and polished them gently and all has been well for about a year.
Hope this helps,
Russ

Woody1 · Post by **Woody1** » 11 Jul 2003, 22:10

I had a similar problem with my 406 2.1 TD. Depending on your model a transducer unit or a standard cable drive unit is fitted.
Mine was a transducer which is situated down near the gearbox.
Apparently this is a very common fault and it needs replaced as it controls more than just your speedo in the car, fuel consumption being one of them.
A new one is about £30

ianb · Post by **ianb** » 25 Sep 2003, 15:51

To revive this post -
After taking out the binnacle & cleaning any obvious contacts the speedo behaved itself until now...
symptons:
As before the speedo flutters , drops to zero for a short time then picks up again,
new - sometime the rev counter and/or fuel gauge will also flutter in sync with the speedo - but just once then keep reading (the trip meter resets to zero when they all do it)
elec. windows & sunroof operate ok when this happens & it doesn't noticeably affect the engine ,
I'm loath to go to a Peugeot dealer except as a last resort so any ideas anyone please?
Thanks
Ian

mbunting · Post by **mbunting** » 09 Aug 2006, 09:58

Interesting reading this thread, I have the same problem, don't know whether it's cable or electronic drive, but it used to be a taxi, and I read somewhere that these must be cable drive ( something to do with the meter ? )

Anyway, my problems point to an electical problem - the trip and mileometer work without a problem, but the speedo needle and the rev counter are either stuck above zero ( ign on - return to zero when off ), or stuck at a particular rpm / speed, or working ok ( usually only one of them is working - press the plasic or the trip reset and the other one may burst into life ).

Can't validate the hot/cold because it's summer at the moment, so it's always hot ( supposedly

).

So this idea about the link between two boards is getting me interested, time to have a look !

mbunting · Post by **mbunting** » 10 Aug 2006, 17:12

Right then, my speedo is electronic, I've taken it out over lunch ( approx 15 mins to do ) - quite easy really.

It's Sagem, and I've had a look at the back, where you can clearly see the connection between the two layers which is actually behind the rev counter.

The connection itself is a bit of PCB sticking out, with the ribbon pcb type membrane looped over, and then held on by a springy bit of metal which pushes the connectors on the ribbon onto the connectors on the pcb - obviously cleanliness and alignment are important here.

Cleaned them up with electrical cleaner, and will be putting it back in the car shortly ( still at work

).

Interestingly, this makes replacing dash bulbs very easy - not the pain in the arse effort of previous models.

Will post up later when I get home

mbunting · Post by **mbunting** » 10 Aug 2006, 19:15

Right then,

It was still intermittent at first, the bulb for the mileage backlight has gone ( although the miles still show ), but eventually it all settled down, and both the speedo and rev counter worked as they should.

Going out again shortly, so that will be the proof of the pudding etc.

I was 99% certain it wasn't the sender below the glovebox because it occasionally worked fine when you applied pressure to the bottom of the instrument panel - or pressed the trip reset button hard - indicating perhaps a dry / loose connection on the back of the panel.

This board is a great mine of information

ianb · Post by **ianb** » 11 Aug 2006, 21:57

Blimey - I started this post about 3 years ago - I'm still running the same 1.8 16v 406.... and I'm still getting intermittent speedo probs.

To be honest , after taking the binnacle out 2 or 3 times and then everything going fine for a few months, I sort of grew to accept it as a French electronic quirk, mechanically the 406 is tough as old boots and mine has certainly given good value on that front (now up to about 148k), perhaps I should get round to looking at the speedo again one of these days...

Adstar · Post by **Adstar** » 22 Aug 2006, 10:23

I have the same speedo problem with a 96 605. I have been advised to take the sender unit off the gear box and either clean it up or replace it! Apparently it could be dirt in the 'reader' or a looe, faulty connection from the sender.

Mine seems to be effected by moisture and cold starts!

Would be interesting to know how it is effecting the mpg? Or is that just a referal to the fact the mile counter doesn't count when the speedo isn't working!?