Air con compressor not kicking in

[benzsupra]

Hi everyone, newbie with questions how original!
Just brought myself a W210 e300td. When i got it i put the air con on and it appeared to get slightly colder so i just put it down to a re gas.... Had it re gassed today and there was no leaks and it has been fully gassed and oiled up but it wasn't making any difference. It is only now i realize that where the air con compressor is supposed to kick in periodically and you hear the revs get higher, this doesn't happen. I called a specialist and he said it sounds electrical but i checked the fuses and they are fine. now it has to be wiring or compressor unless anyone has any other ideas? does anyone know a test i can do to see if it is either of these? The specialist started talking about running a feed from the battery to one of the top up pipes to see if the compressor kicks in??? anyone heard of this?

Help please.....

Thanks for reading,
Ben.

 

[Dieselman]

Daft question but you are running the system with the EC light OFF aren't you?

 

[benzsupra]

no i thought it had to be on for it to work? i'll try it with it off and see what happens. i know it doesn't actually get cooler with it off but i'm not sure if the revs change or anything. be right back!

 

[benzsupra]

doesn't seem to make any difference to be honest... no change in the revs or anything, just seems as if there is no compressor at all

 

[Dieselman]

You won't notice a change in revs on an E300, just a very slight kick.

Leave it on for a while on recirc and the temp dials set to cold. If you don't come back in we know you've frozen.

 

[benzsupra]

defo no difference, light on or off or on circ....

 

[television]

For models 129,140, 202, 210, 215, 220, 463 Up to the 15-08-99


If you have the EC light on all of the time on the above cars, the cure is to replace the temperature sensor.

This sensor for the refrigerant leaks moisture so that incorrect values are transfered to the control module and air con is turned off.

Replace sensor.
__________________

 

[benzsupra]

Where abouts is this sensor? are there any diagrams and do you have any part numbers?

 

[benzsupra]

I see the diagram on the sticky on the other website but what part is it? it's not very clear.

 

[television]

65 in the link I believe, do double check first these things are not my best points

http://www.detali.ru/cat/oem_mb2.as...GM=717.446&CT=F&cat=45P&SID=83&SGR=195&SGN=06

 

[benzsupra]

Thanks mate, i'll still go and have it checked by the pro's but at least now i ain't going in clueless.

 

[television]

Thanks mate, i'll still go and have it checked by the pro's but at least now i ain't going in clueless.

Its a pleasure, I know what you mean by that, I hope that you get it sorted

 

[jaymanek]

For models 129,140, 202, 210, 215, 220, 463 Up to the 15-08-99


If you have the EC light on all of the time on the above cars, the cure is to replace the temperature sensor.
__________________

The EC light staying on just means there is an error in the system, why do you say specifically that its the temp switch, could be anything...

Also he can turn the light off so not that...

best to get it onto an A/C machine and see whats actually going on..

 

[television]

The EC light staying on just means there is an error in the system, why do you say specifically that its the temp switch, could be anything...

Also he can turn the light off so not that...

best to get it onto an A/C machine and see whats actually going on..

I put this up as its a known MB mod and it is recomended. I agree it could be anything but if it is kooked up it could show the sensor to be the problem,

I did say at the end that it cures EC light locked on

 

[richard]

Hi,

remember if you replace anything, inc temp sensor (certainly on the ML, where its a temp. and pressure sensor), you have to have the car regassed - which costs about £45 from an appropriate tyre place.

If you're being nice to the environment, you should have it de-gassed properly (gas is pumped out into container) by them first, rather than just undoing the temp sensor and sending the gas into the sky - particularly important on older units where the gas is really bad stuff.

My ML had stopped working, what had happened is the front radiator thing (can never recall whether this is the evaporator or condensor) had leaked - you could see the oil on the bottom, working its way up. New radiator-thing and a re-gas as good as new.

If you have the aircon with the lcd display, you can get into test mode (I can't remember how, perhaps someone else can) and look at refrigerant pressure when engine off, if its at 1 bar, theres no gas in it. Of course, no gas means a leak somewhere, the oil gives it away if you're lucky, else its a dye job

Given what television says, perhaps I should have replaced the temp/pressure sensor at the same time

Richard

 

[BlackC55]

Have a look at the compressor signal wire. It is a single wire that goes to the top of the compressor. Is it still attached? They often break off.

 

[jaymanek]

Have a look at the compressor signal wire. It is a single wire that goes to the top of the compressor. Is it still attached? They often break off.

and if you have a little voltmeter see if its getting a posi feed when the EC light is off, fans on and car is running......

 

[benzsupra]

I can turn the light on and off so maybe not a temp sensor. I am taking it to a specialist tomorrow but i'll check the voltage on that wire first, it is attached but what sort of voltage am i looking for? will it be 12v? I did have it gassed up and i have a printout stating the correct amount of gas and oil in the system with no leaks. It also shows that the amount's were not that far off full to start with. After reading possibly every air con related post on this forum i'm starting to think maybe the condenser but i'll see what the man in the know tells me. As soon as i know i'll keep you posted.
Thanks guys.

 

[benzsupra]

Just to let anyone know and to close this thread i solved the problem, it appears the washer bottle had been previously removed and instead of re-fitting it properly it was forced in severing the wire between the bottle and the car! Re connected and voila! i got cold air for the coming winter So if anyone has similar problems that wire is always worth a check. Not 12v running to it though, i can't remember the exact voltage but it's about 6-7v. Just for future reference.

Thanks for all the help guys.
Ben.