non commital indecisive speedo!

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I think i have found the answer, but I want confirmation before getting my hands dirty!

96 Peugeot 605 2.1TD

The speedo doesn't like cold mornings, sometimes it doesn't bidge, sometimes it registers the fact I am moving, sometimes it is even generous enough to show me just how fast I'm going!

I was told it is plastic gear drive in the gear box. But in my view that would cause problems every time the car was started ( I haven't had a problem on the trip home after work!) Which is why i suspected an electrical fault.

Searching through the site lead me to a similar problem on a Citroen. That has an electrical pick up from the gearbox. The solution was to remove clean and replace. Significantly more doable than replacing little plastic gears!

So, simple question, is it true!? Am I lucky enough to have an electric signal that I can clean the contact of, or am I stuck working out the speed on the rev counter (I'm getting quite good now!).

Thanks in advance.

[rotodiesel]

The easiest way to tell if you have the electronic speedo is to turn off the engine at (say) 20mph and coast to a halt. The usual safety precautions concerning loss of power assistance to brakes and steering must be obseved.

With the electronic speedo, the speed at which you turned off the ignition will remain displayed, even when the car is stationary. When you next turn on the ignition, the pointer will "motor" down to zero.

The connections to the hall sensor on the gearbox (near driveshaft) are suspect - unlatch and part connector, apply vaseline to pins and mate/unmate 5 times. The connector to the pc board behind the dash are not wonderful either, but live in a better environment. Try the gearbox end first.

rotodiesel.

[Homer]

With the electronic speedo, the speed at which you turned off the ignition will remain displayed, even when the car is stationary. When you next turn on the ignition, the pointer will "motor" down to zero.

If this is true then the speedometer is illegal as it has to be accurate to +10%+6.25mph at all speeds over 25mph. Nothing about having the engine running.

[philhoward]

Every car i've driven with an electronic speedo has seen the needle crash to zero as soon as I've turned the ignition off (for testing purposes only..), then return to the current speed when the ignition turned back on whilst moving...on an empty motorway of course!

[Linchpin]

Yup... thats what my 306 XSi one does...

Ignition off > Dead dashboard (inc speedo).

No holding on speed or anything like that.

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WooHoo Contraversy at last! I haven't tried the experiement, but was more than a little dubious. I'll just keep asking around and eventually get my hands dirty.

Does anyone actually know what type of 'feed' these cars are fitted with? Is it electric or mechanical.