Mercedes owners did you know?

Feb 24, 2013
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It is probable that most of you will already know this, but if I only enlighten one more it is worth the trouble

We have driven Mercedes for a good few years, on most models until fairly recently the air con control button also has the word 'rest' on it

I have known for some time what this did but just recently have discussed with a few Mercedes owners, my FIL included who has driven one for 15 years, and they have not known



So if you have the word rest on one of your buttons, it can be used to help maintain the cabin temperature after you have turned off the ignition

Brilliant in hot and cold weather, when you stop, only after the key is removed if you press the rest button a red light comes on and you will hear the fans run, provided there is sufficient heat or cold in the air con, and the battery is good, it will do its best to maintain the temperature you had set

Typically it runs for no more than 15 minutes, but it is amazing how much difference that can make on very hot or cold days

We have a Mercedes chassis on our MH with the same feature, as we arrive on site we press said button it uses up the heat / cool while we set up the electrics or heater

Apologies for those that already knew and have just wasted a few minutes reading this, sympathy to those who are not fortunate to have a Mercedes :D and enjoy the benefit the few who maybe did not know, or knew but had forgotten (y)
 
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Mousy

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Sep 13, 2013
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Too late to creep out onto the drive in my nightie, but I'll look tomorrow to see if we've got said button. Cheers David.
 

DuxDeluxe

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Don't have this in the van. Mainly because it is a Fiat, but also not in the car either, which is a Mercedes. However, in Eco mode with the start/stop, the climate control continues to run, so would guess that the function still exists, but just in a slightly different way
 

dabhand

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Feb 19, 2014
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It is probable that most of you will already know this, but if I only enlighten one more it is worth the trouble

We have driven Mercedes for a good few years, on most models until fairly recently the air con control button also has the word 'rest' on it

I have known for some time what this did but just recently have discussed with a few Mercedes owners, my FIL included who has driven one for 15 years, and they have not known



So if you have the word rest on one of your buttons, it can be used to help maintain the cabin temperature after you have turned off the ignition

Brilliant in hot and cold weather, when you stop, only after the key is removed if you press the rest button a red light comes on and you will hear the fans run, provided there is sufficient heat or cold in the air con, and the battery is good, it will do its best to maintain the temperature you had set

Typically it runs for no more than 15 minutes, but it is amazing how much difference that can make on very hot or cold days

We have a Mercedes chassis on our MH with the same feature, as we arrive on site we press said button it uses up the heat / cool while we set up the electrics or heater

Apologies for those that already knew and have just wasted a few minutes reading this, sympathy to those who are not fortunate to have a Mercedes :D and enjoy the benefit the few who maybe did not know, or knew but had forgotten (y)
See the Lincoln 2014 thread and my flat bloody batteries!
 
OP
DavidG58
Feb 24, 2013
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Don't have this in the van. Mainly because it is a Fiat, but also not in the car either, which is a Mercedes. However, in Eco mode with the start/stop, the climate control continues to run, so would guess that the function still exists, but just in a slightly different way
That's interesting our newest Mercedes is a Hybrid E300, the Hybrid bit may be the reason that one doesn't have the feature, but I will check again, it definitely does not have the REST on any buttons
 
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DavidG58
Feb 24, 2013
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See the Lincoln 2014 thread and my flat bloody batteries!
I saw this thread, but cant really think the reason for your flat battery could be this 'feature', is your MH on a MH chassis?

If so did you press the REST button when you stopped?

I guess it is possible the stop signal does not function any more and it might keep going till flat, but my understanding is it looks at voltage and air temperature, so for both sensors to fail would be really bad luck
 
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FJmike

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Jul 17, 2014
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Ive been using this feature on my 2007 Sprinter based Pilote since we bought it. Suprisingly it is mentioned in the manual:D.In the winter it keeps the van warm until the truma is up to speed.
 
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DavidG58
Feb 24, 2013
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Ive been using this feature on my 2007 Sprinter based Pilote since we bought it. Suprisingly it is mentioned in the manual:D.In the winter it keeps the van warm until the truma is up to speed.
:) Agreed,

but I never read them till things go wrong, technically if you don't know about the switch it hasn't gone wrong it is a feature you might have missed (y)
 

FJmike

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One feature I've never been able to suss out is the auxillary heater, like how do you get it going????????
 

FJmike

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I was just looking at your photo and my rest button is to the side of the temp controls.
 
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DavidG58
Feb 24, 2013
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I was just looking at your photo and my rest button is to the side of the temp controls.
my photo was lifted off google images, too dark to go out when I wanted to post

I have just seen temperature is in farenheit not centigrade, guess it must be a US spec

other than that I think ours is pretty much as the photo, but I might be thinking about my car not MH :)
 
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DavidG58
Feb 24, 2013
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One feature I've never been able to suss out is the auxillary heater, like how do you get it going????????

to the left of the steering column on our MH there is a rocker switch looks a bit like a heated rear window symbol, I think a red light comes on the switch when on

this is the one I think runs the aux heater, but really not totally sure it is the right one

I presume it is not in your manual :D, not even looked in ours (y)
 

DuxDeluxe

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That's interesting our newest Mercedes is a Hybrid E300, the Hybrid bit may be the reason that one doesn't have the feature, but I will check again, it definitely does not have the REST on any buttons
mine is the C250 diesel - which has start stop and I suspect that it all happens in the background on yours similar to mine
 

dabhand

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I saw this thread, but cant really think the reason for your flat battery could be this 'feature', is your MH on a MH chassis?

If so did you press the REST button when you stopped?

I guess it is possible the stop signal does not function any more and it might keep going till flat, but my understanding is it looks at voltage and air temperature, so for both sensors to fail would be really bad luck
The truth of the matter is we don't exactly know what happened, but it's a hymer and the rest button was on at "sometime" over the weekend, cos the red light was on but don't know how long for. It's never happened before so I am just assuming something all consuming (power that is) was left on and then switched off.
 
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DavidG58
Feb 24, 2013
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Bolsover, Derbyshire
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The truth of the matter is we don't exactly know what happened, but it's a hymer and the rest button was on at "sometime" over the weekend, cos the red light was on but don't know how long for. It's never happened before so I am just assuming something all consuming (power that is) was left on and then switched off.
Interesting, but it should time out or be voltage / temperature monitored somewhere you would have thought, we use ours all the time, the longest I have ever seen it stay on was about 20 minutes

edit - when the engine is running if you press the rest button the red light comes on to indicate air con is turned off

was your red light still lit even when the battery was flat before jump starting?
 

dabhand

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Interesting, but it should time out or be voltage / temperature monitored somewhere you would have thought, we use ours all the time, the longest I have ever seen it stay on was about 20 minutes

edit - when the engine is running if you press the rest button the red light comes on to indicate air con is turned off

was your red light still lit even when the battery was flat before jump starting?
No, there are so many ponderables that it will drive me nuts, eg started the generator on Sunday afternoon for 10 or 15 mins, did this start off a chain reaction - ah I hear you ask, but probably not, if the fridge doesn't relight on the gas, can it stay on 12v? my understanding is it can't if it's a 3 way fridge and will only go to 12v when engine running,
So everything seemed in order, went to funsters marquee on Sunday night had far too much to drink, indulged in way too much puerile and churlish banter (actually that bits not true) and generally had much merriment and amusement, battery must have been ok on return as lights worked, then awoke far too late on Monday with the the 12v switch in the off position when flicked back on the battery alarm light flashed briefly and everything remained, defunct, as they say. So, as I say, not really any fudgin idea!
 
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