EC Rest Button stays lit

[mallorn]

Hi, as a newbie here, I've tried searching these forums but to no avail.

I have a 2000 'new' model C200K (one of the first off the line), with about 60k on the clock. Recently the 'EC Rest' button has stayed lit.

I'm guessing it's an aircon problem, can anybody give me some clues?

Cheers from a newbie.

 

[rajinder_1]

if it is staying lit then its something fairly big, ie pump motor or something, not the case of a regas i think, or thats what ive been told. Best thing it to get it on a diagnostic machine to see what the faults are.

 

[mallorn]

Thanks mate, I'll get it checked.

 

[frog1520]

I'm sure I've read of the light being on sometimes when its just needed a regas....

 

[sportyreptile]

There has to be a minimum amount of refrigerant and pressure needed in the system before it will run, if it's all leaked out the aircon pump won't run.

It's a self presservation system "feature" if you like, as well as refrigerant in the system there's a lubricating oil as well, run a pump without oil and it'll literally grind to a halt pretty quickly.

Most likely cause of a leak is either at a joint in a pipe or the bottom of the condensor has failed, condensors are about £120-£150 and a regas about £50 depending on who you use.

 

[massssoud]

I had a similar problem on my 2000 S500. According to its handbook it is to prevent damage to the compressor when there is not enough refrigerant.

As your car is about 6 years old, it is normal to lose some refrigerant.
On my car I just refill it and there was no leak, But it also needs a star diagnose to reset the air conditioning.(not sure if C-class needs to be reset)

Hope it helps

 

[jaymanek]

Could be anything, but the very fact that you need a regass suggests that there is a leak somewhere.

Have you been running the Air Con over winter or did u set it on EC? If you turned it off then that was not a good idea as it will lead to rubber parts drying out and causing leaks.

Go and get it checked asap.

Cheers

 

[mallorn]

Thanks for all the info guys, I have a Merc friendly local garage, so I'll get them to check it out.

And no, I tend to run it with aircon on all year, only resorting to 'EC Rest' if I'm doing a long run and want to save some fuel.

I do recall the missus commenting that the aircon 'smelt musty' so maybe it is a regas.

Cheers

 

[Shude]

There has to be a minimum amount of refrigerant and pressure needed in the system before it will run, if it's all leaked out the aircon pump won't run.

Yet mine had practically no gas left in it at all and happily ran (albeit totally ineffectively) without complaint.