Citroen XM Forum

A man after my own heart Robert. Is there any truth in the rumur going round the CCC that you have resigned as XM columnist to pursue your life long ambition to become proprietor of the largest scrap metal dealer in western Europe?
If this C5 was a dog it would of had THE trip to the vets by now.
Not as bad as the Renault Van we have here at work, it went in for its quarterly injector seal replacement two weeks ago, got it back yesterday and two seals have failed with 18 miles of use

I can feel it coming


D

imgur

Swedish Steel is so much heavier than French Steel!

Dean I just explained your symptoms to a Citroen guru who prefers to remain anonymous , but who said this in response:

What I am going to tell you may cure it BUT BE CAREFUL -
Remove the positive lead from the battery and join the power lead to the earth post of the battery with spanner or something, BUT do not allow it to touch the positive post of the battery. Hold for about 30 seconds then replace the lead to the positive post. Now lock the car and walk away some distance, (about 50 yards) to break the link between the key and the transponder. Return to the vehicle, unlock and start the engine and it should reset everything

As bizzare as that sounds, he said he's seen a ton of them over the year with those symptoms and in many cases the above has cured it.
I have no idea why that battery post thing would work but it seems you can't loose anything by trying.... (unless you accidentially allow it to touch the positive post )

I suspect that doing that takes the positive rail in the cars electronics down to earth.
That should clear any residual voltage in the electronics.
Takes very little voltage at virtually no current to lock up modern electronics.
In digital computer circuits 0 to around 2 volts is seen as zero while 2.5 to 6 volts will be seen as a one.
The BSI programme seeing a one where it should see a zero could be enough to upset the programme.

Earthing everything is standard practice on an electronics work bench these days.
I use a large alloy sheet on the bench top with two earth tags.
One earth lead goes to and earth point on the soldering iron stand.
The other earth wire to a conductive wrist strap.

John

C5s are now like XMs used to be, if anything goes wrong that's difficult or expensive, go and buy another one and keep the original for spares.

Peter

And so on until you have a dozen cars Peter

xmexclusive wrote:I suspect that doing that takes the positive rail in the cars electronics down to earth.
That should clear any residual voltage in the electronics.
Takes very little voltage at virtually no current to lock up modern electronics.
In digital computer circuits 0 to around 2 volts is seen as zero while 2.5 to 6 volts will be seen as a one.
The BSI programme seeing a one where it should see a zero could be enough to upset the programme.

Earthing everything is standard practice on an electronics work bench these days.
I use a large alloy sheet on the bench top with two earth tags.
One earth lead goes to and earth point on the soldering iron stand.
The other earth wire to a conductive wrist strap.

John

I have used this method of shunting to Gnd on complex circuit boards. It works.

Green crusher, eh? Must be LHM-powered!

xmexclusive wrote:I suspect that doing that takes the positive rail in the cars electronics down to earth.
That should clear any residual voltage in the electronics.
Takes very little voltage at virtually no current to lock up modern electronics.
In digital computer circuits 0 to around 2 volts is seen as zero while 2.5 to 6 volts will be seen as a one.
The BSI programme seeing a one where it should see a zero could be enough to upset the programme.

Earthing everything is standard practice on an electronics work bench these days.
I use a large alloy sheet on the bench top with two earth tags.
One earth lead goes to and earth point on the soldering iron stand.
The other earth wire to a conductive wrist strap.

John

That makes perfect sense, thank you John.
Something I should have known really, working in IT, we've had about 500 of a particular Dell model lately which tends to lock up every couple of months, either that or the network card disappears. The only thing which fixes it is powering off, unplugging the PSU and holding the power button for 10-15 seconds to dissipate any residual charge on the board, same thing I suspect.

I never did think a car would be as susceptible to this kind of thing, but why the hell wouldn't it be, given that even vehicles of Mk1 C5 vintage are essentially computers on wheels.

More and more of this type of nonsense to look forward to as time goes on then

Ciarán