Not 406 related,

[lozz]

Anyone on here heard of Blocked pollen filters causing electrical problems in french cars?
Yesterday itook the climate control panel out in My ca r 04 lag, as one of the ilum bulbs wasnt working, they turned out to be smds so that was a waste of time


whilst having alook at it, ifound the Main thick cable which controls the heater blower getting hot, black scorch mark on the wire,
iwas just going to change the control panel , but someone said, dont bother it will just burn again,
it will be the pollen filter Blocked, how ever the heater blows fine,

Question is how can ablocked filter cause a wire to burn ?

[plod]

Not my area of expertise, but I should imagine, a blocked pollen filter would put extra strain on the motor as it's having to work harder, and thus loading up the wiring more, hence the scorch marks

[Doggy]

On the contrary, restricting the air flow reduces the work done by the fan, (that's why vacuum cleaners turn faster when you block the pipe).

I think it's more likely that the wiring's inadequate to start with and blaming a blocked pollen filter is a convenient way of finding some explanation or implicting the poor owner.

[Welly]

On the contrary, restricting the air flow reduces the work done by the fan, (that's why vacuum cleaners turn faster when you block the pipe).

But turning faster is drawing more current? hence the heat?

Another important factor is motor-cooling, if the pollen filter is well blocked then the airflow through the fan/motor is reduced which makes it run hotter.

Hold your hand over the end of a vacuum cleaner hose (or I'm sure puggy can think of something else to use ) and if you left it there for ages the motor would burn out through lack of motor-cooling airflow.

S'wot i finked anyway

[lozz]

Thanks,
iwill change pollen filter and see if the heat in the wire cools down abit,
the wire dont get hot unless the Blower is on no 4,

ihate french electrics,

[Coops]

Lozz, Renaults tend to have a few problems with heater wiring, as I've found out after my 406 went to the great scrapheap in the sky The following link takes you to the Renault forum I now tend to frequent http://www.renaultforums.co.uk/showthre ... 83&page=43, the site is not quite as user-friendly as this one (only 5 posts per page) but the people who post there match up to those who answer the numerous questions for the 406. Whilst this link is Scenic specific, it would seem that the first sign of problems is the loss of blowers on the various settings. It's been traced to the wiring getting too hot and eventually melting the plug. Now i'm not suggesting that your Laguna is going the same way, but it might be worth trawling through the Laguna section http://www.renaultforums.co.uk/forumdisplay.php?f=105 to see if it would answer your question.

Cheers

[lozz]

Cheers coops,
ive been a member on the Rf for afew years, idont go on there much these days tho,

[Doggy]

On the contrary, restricting the air flow reduces the work done by the fan, (that's why vacuum cleaners turn faster when you block the pipe).

But turning faster is drawing more current? hence the heat?

No. Resistance remains the same, but the effective voltage, in a dc shunt motor = applied voltage - back emf generated by the motor.
The faster it turns, the greater the back emf and hence the lower the current. Same is true of the universal series motor in your hoover, or, for a different reason any induction motor.

....but you are right about the heat - I was just trying to give an example familiar to everyone.

Another important factor is motor-cooling, if the pollen filter is well blocked then the airflow through the fan/motor is reduced which makes it run hotter.

Hold your hand over the end of a vacuum cleaner hose (or I'm sure puggy can think of something else to use ) and if you left it there for ages the motor would burn out through lack of motor-cooling airflow.

S'wot i finked anyway

[lozz]

Update, ive sorted the overheating wire, thanks all,
it was indeed the Blocked pollen filter, heater blows alot better now, also my aircon as burst into life, another thing ididnt expect to get working,

ive also got the Broken spare key card working with a bit of soldering , saved me buying anew spare one at 180 quid

Edit: forgot to mention, pollen filters clean well in the washing machine,