doing 41 mph all the time???

[Roylewaa]

Just happened today the speedo has gone a bit haywire in my D8 today, it starts off at 0 when I pull away, flicks up and down a couple of times then jumps to 41 and stays there

Any ideas where to start looking first, is the connections for the speedo under the carpet in the footwell as on the D9?

Im fearing ive disturbed something when I was trying to diagnose the idling problem under the bonnet as it worked perfectly before that
cheers for any info

[Gary406]

sounds to me like your cluster needs a good solder.

on 406s is a common issue. the solder joints on the circuit board inside the clocks go dry causing them to behave like yours are ..

its a case of taking the clocks out and touching all the solder joints with a solder iron
this heats them up and re-melts the solder back together .

[Doggy]

There's a black box behind the glovebox that's usually implicated in this form of deception. I recommend rehabilitating a well-behaved equivalent from your local scrappy.

[Roylewaa]

There's a black box behind the glovebox that's usually implicated in this form of deception. I recommend rehabilitating a well-behaved equivalent from your local scrappy.

Funny you should mention that, ive been messing around behind there yesterday replacing the damaged white connecter here (its currently not connected so no blowers at the mo, I knocked a black box and it dropped down aswell along with moving things out of the way to remove the recirculating flap black box thats a gonner

[plod]

There's a black box behind the glovebox that's usually implicated in this form of deception. I recommend rehabilitating a well-behaved equivalent from your local scrappy.

Funny you should mention that, ive been messing around behind there yesterday replacing the damaged white connecter here (its currently not connected so no blowers at the mo, I knocked a black box and it dropped down aswell along with moving things out of the way to remove the recirculating flap black box thats a gonner

Mine looked like that, shorting out like that
Mate said I was lucky car hadn't caught fire

[Gary406]

were is that plug ?

[plod]

Up behind glovebox

[Gary406]

cheers dave. im gonna inspect mine cos that looks really dodgy.

can run a wire as well through gromit to battery while im at it.
finally wire my battery meter incidator thingy up ..

[plod]

Reminds me, I never sealed the feed coming through the gromet

[Gary406]

sealed ?

[plod]

I made a small hole in the gromet to allow the wire through, but I never put any sealant on the wire to prevent water ingress

One of them jobs keep meaning to do, but procrastinating for england

[Gary406]

OMG can water get in there ?

i dont even have a gromet on anymore

i have a 4 gauge power cable a 8 gauge power cable . about 5 alarm wires running through it

[Roylewaa]

Must admit, I got quite a shock when I saw the connector, Its even worse inside all black and burnt, the damage goes up the wiring on either side about 2 inches I only noticed when I had the blowers on I got a burning plastic wiff for a few seconds

What could have caused the connector to burn like that, is it a high voltage through there?
I'm going to be using chocolate blocks to put the new connector in with them covered in insulating tape, would that be ok

[steve_earwig]

Not high voltage, it can't be above 12 volts, it's high current - presumably the fan motors in these are quite powerful and a dodgy connection (on a Peugeot, I don't believe it!) means that there's a small bit of resistance there which is being made into a heater by the amount of current being passed. A quick Google later, apparently heater blowers are something like 300 watts, which, using P=IV, at 12 volts is 25 amps. which, using V=IR, means the fan has a resistance of 0.48Ω, introduce to that circuit a resistance of say 0.2Ω in the connector and, using V=IR again, the circuit current drops to 17.6 amps but that 17.6 amps is going through that 0.2Ω dodgy connector, using V=IR yet again the voltage across it has dropped to 3.5 volts (think of the fan motor now being a volt drop resistor for the connector), this time using P=IV once more, that dodgy connector is dissipating 62 watts. See a heat sink on it?

Those "chocolate block" connectors go up to 30 amps, which is a hell of a lot of power in your house, however the wires in your house are single core and can't go anywhere when you tighten a screw, but in your car the wires are multi core so I'd feel happier if the ends of the wires were soldered, even better twisted together and soldered with heat shrink tubes around the joins.

[Roylewaa]

cheers for that info, I contemplated twisting the wires together but they're very think wires so think they would be a pain to twist together?