Fan ressistor c5 2009

[Sufii]

I don't know. I have to do it every so often to my car - it's actually stopped working at the moment and I'm looking for a good day to "go through the process".

So you just jump the fan and reconnect the ressistor? How much time do you get climate each time?

[xantia_v6]

The speed control module has a soft-start action, so that when the system is switched on, it does not apply a sudden pulse of power to the fan, but gradually increases the current to the required level for the selected speed. It also has an over-current protection, so that the fan cannot take too much current if there is a fault in the fan or wiring.

I think that your real problem is that the bearings in the fan motor are too tight due to lack of lubrication and maybe rust, so that the fan does not start spinning with the soft-start, and then the current protection kicks in before the motor has developed enough torque to get the bearings moving. Feeding the fan with the jumper wire gives the motor a much bigger kick of current which gets everything moving, and for at least a while, the motor will then start with the normal controller action.

If this is the case, then the fan motor will eventually need to be replaced, or at least the bearings lubricated. I don't know if lubrication is possible on these.

[Paul-R]

That's very interesting and a possible good explanation.

[GiveMeABreak]

Ok guys, tried to jump cable between these two point as Paul recomnended. And the fan is working on full speed! Thats a good sign.
But what know? Should I buy a Brand new ressistor? With ort number 6441AJ?

6441AJ is the actual Blower Motor. 6441S7 is the Resistor.

Good result for now though.

[Paul-R]

An epilogue of my own.

My own heater blower motor stopped working a week or two ago (I'm not using the car as much as I used to and it can be a week between uses) and it was working when we went to France at the end of October. I did the simple trick, ran the motor for a few seconds using the shunt, and now it works as it should.

Total time taken including the faffing around to get the underdash panel back in place - about 15 minutes max.

[myglaren]

I'll have to try that with my daughter's C3

[GiveMeABreak]

So as Mike says - I wonder if it is indeed the moisture building up and causing some rust that prevents the slow speed start up. It would make sense if this is happening only after a delay in use.

[white exec]

Bearings in blower and similar motors do dry out over time. Phosphor-bronze bearings hold oil, but eventually go dry. A new squirt of thin oil* can give a new lease of life. Access is often the issue.

* Don't use old-style 3-in-1, it has a reputation for going gummy/varnish-like. Use an oil which states 'non-gumming', or even a 0?5W-30 engine oil.

[Paul-R]

Hmm, how easy is it to get to the bearings to lubricate them? Hopefully not motor out which means dashboard dismantling.

As an alternative I'm seriously thinking of wiring in a push button to short the two thick wires together when needed. I'm just a little concerned about the fact I'd be leaving the control unit wired up while I did that.

[Paul-R]

I've not heard about the 3-in-1 oil problem. Maybe sewing machine oil then?

[white exec]

As an alternative I'm seriously thinking of wiring in a push button to short the two thick wires together when needed.

I did muse about a Panic Button, but maybe no substitute for a bit of lubrication.

[myglaren]

I've not heard about the 3-in-1 oil problem. Maybe sewing machine oil then?

Or maybe some of Malcolm's much-lauded Duck Oil.*







* No ducks were harmed in the manufacture of this product.

[white exec]

Sewing machine oil gets over the gumming problem.
Sunoil* also made a better alternative to old-style 3-in-1. Could be the problem is now sorted.

Of you think back to old 3-in-1 cans, with the vertical polythene spout, you might remember a yellowy varnish-like remains on the top of the can, where the oil had evaporated and left a thick gum behind. This might jave been good for waterproofing lawn-mowers, but wasn't at all helpful on lightweight equipment.

* No suns were harmed...

[Paul-R]

I did muse about a Panic Button...

[Hell Razor5543]

Sir Terry Pratchett covered the point quite well. In one of his books there was a comment along the lines of;

"If you had a button that, when pressed, would destroy the world, and you painted a sign that said "Do not press this button; it will destroy the world" the paint would not have enough time to dry before somebody pressed the button to see what it did".

In another book Archchancellor Ridcully had good reason for a door to be nailed up, with a sign that said something like "Sealed by order of the Archchancellor. Do not open". The University handyman left enough space to get a prybar under the nail heads, for when somebody wanted to see what the fuss was all about.