Switch beside cigar lighter - W210

[surreychris]

Hi All

I have asked this question before but never got a definitive answer and it has always puzzled me.

In the ashtray compartment of my 2001 W210 E220cdi I have a switch next to the cigar lighter. It has a straight line with some wavey lines above it.

What is this switch, what is it meant to do and when is it on/off?

I think someone mentioned before it is something to do with a heating boost tho whether it is on/off lit/not lit it seems to make no difference

Any clear answers?

Thanks

Chris

Ps. times like this I wish i had a handbook for the car

 

[StevenN]

Its the pre-heater switch.
I have seen other info on here that says that the light off means on.
It should give warm air out the vents within a few mins of starting.
But it has an effect on the mpg.

Regards

Steve

ps I have a similar motor if there are bits of the manual you need just ask and I will try to scan and send.

 

[fah320]

Yes it is an electric unit which is supposed to heat the coolant and give heat in the cabin quickly but most dont work. I will appreciate if someone has an idea how to get it work properly gives an explanation...

 

[renault12ts]

Its the pre-heater switch.
I have seen other info on here that says that the light off means on.
It should give warm air out the vents within a few mins of starting.
But it has an effect on the mpg.

Regards

Steve

ps I have a similar motor if there are bits of the manual you need just ask and I will try to scan and send.

It is a heater, yes...but not a pre-heater.

 

[StevenN]

Hi Renault21ts

Can you explain my error?

My thinking was it pre-heated the air out of the vents until the hot water of the engine takes over.

Ta

Steve

 

[renault12ts]

These cars also came with a programmable heater which pre-heated the air. The electric heater only works below a certain temp, when the car is running. It heats the coolant water.

Mine doesn't work...most don't.

 

[fah320]

These cars also came with a programmable heater which pre-heated the air. The electric heater only works below a certain temp, when the car is running. It heats the coolant water.

Mine doesn't work...most don't.

Mine neither

 

[surreychris]

Thanks all
So I should keep my switch lit up and save some mpg.

Seems a bit silly that the engine has to be running which will in turn heat the coolant anyway.

Thanks

Chris

 

[Diesel Benz]

Mine neither

But you seem lucky because often these drain the battery, and very quickly, when they get broken. Or perhaps your heater has been disconnected, you should not need it anyway in Turkey.

Thanks all
So I should keep my switch lit up and save some mpg.

Seems a bit silly that the engine has to be running which will in turn heat the coolant anyway.

But it was already explained that the electric heater helps you getting warm air from the heater before the engine warms up and is able to supply sufficiently hot water.

You may save a bit fuel although probably not much because the CDI engine efficiency drops a lot when it runs at a low temperature. The electric heater helps the engine to reach the normal temperature faster. You might be more concerned about the longevity of the engine if you drive it often below the normal temperature (longer than when activating the heater).

 

[englishdas]

Thanks all
So I should keep my switch lit up and save some mpg.

Seems a bit silly that the engine has to be running which will in turn heat the coolant anyway.

Thanks

Chris

I'm confused now... when it's lit up it means its on, or off? Oddly enough, I've been messing about with it lit/not lit for the last few days, and my battery went dead a day or 2 ago, totally surprising me.

 

[StevenN]

light off is heater on

apparently?

steve