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I have never been able to get mine to work on my 2012 E350 M276.... I have packages 1 & 2... but don't have the lane tracking or wheel packages.
Appears it is not programmed in North America, nor is the auto sunroof closing when the rain sensor senses rain, and the reduction of capabilities with the Intelligent Lighting System. I believe it needs some vediamo coding, If anyone knows which control modules to code for tunnel mode then please chime in.
I have the tools necessary to code that but just need some direction as to what options to toggle.
Sounds like an option for Las Vegas Strip cruising.
Everywhere else I keep window close as they create too much noise when open at high speeds.
The only time I open window is at tool booths.
Unless you have a US model, Canadian cars should have tunnel mode (if disabled, it can be activated via Vediamo though. PM me.). It's not a feature that can be coded on US cars, you have to replace the climate control unit. I swapped out my US climate control unit for a European version specifically so I could have REST mode. Tunnel mode was a bonus.
Even if you don't normally drive with the windows open, it's nice to be able close the windows/sunroof with a touch of a button after using the Summer opening feature.
US climate control unit European and US climate control units European climate control unit w/ REST mode
What else did you need to change besides the control panel to do this "upgrade" to what used to be standard?
"rest" mode is REALLY nice to have when you live in wintery climes and need to duck into the store for a bottle of Blanton's.
That's it hardware wise as the aux coolant pump is standard equipment on US cars. Now, the control panel will have to be manually coded (unless you can find one from a car with the same engine/options), but there are companies that offer remote coding now.
REST mode is also nice to use in summer to ventilate the interior when parked.
A very good benefit of the REST function is at any time to have the coolant circulate thru the engine after shut down. This eliminates the “hot spots” inside the hot engine and prevents the coolant from over heating or even boiling. Can only be good for the engine. I would love to have this feature in my E550.
My S550 has it and the only improvement for it could be that it worked automatically every time I stop the car like the Audi Q7 that I owned had it set up. I don’t see how this feature could harm anything if it worked automatically.
ML class at least had the aux coolant pump program to run after engine shut down.
Looks like MB figured out that the same engines in sedans don't work hard enough to qualify for extended cooling.
My newly purchased GLE shuts down front fan with few seconds delay, when sedan kills everything with ignition off.
But then none of my diesels, driven in 110-120F weather will go above 90C
ML class at least had the aux coolant pump program to run after engine shut down.
Looks like MB figured out that the same engines in sedans don't work hard enough to qualify for extended cooling.
My newly purchased GLE shuts down front fan with few seconds delay, when sedan kills everything with ignition off.
But then none of my diesels, driven in 110-120F weather will go above 90C
The problem with hot engine is that when the coolant stops flowing it heats up very fast and in some locations inside the engine can even boil. You can experience this by opening the coolant reservoir right after you stop the hot engine. You can see how the coolant level inside the reservoir raises up very fast until you put the cap back on. I think this is one reason the coolant is lost in the reservoir as with very hot engine it will boil and over flow from the reservoir when it reaches the pressure limit of the system.
I own the W212 for the 4th year and did not have to add coolant yet and again, I operate in 120F for several months every year.
If you have the problem, it likely is something else.
I own the W212 for the 4th year and did not have to add coolant yet and again, I operate in 120F for several months every year.
If you have the problem, it likely is something else.
I have no problem. Just noticed when I flushed the cooling system and filled the reservoir (over filled) to over the divider in the reservoir it quickly went down just below the top of the divider.
I have no problem. Just noticed when I flushed the cooling system and filled the reservoir (over filled) to over the divider in the reservoir it quickly went down just below the top of the divider.
If you overfill it, up to cap filler port... it'll spill out of the overflow line. Otherwise, its not uncommon for the level to drop following a flush as the system purges.
The problem with hot engine is that when the coolant stops flowing it heats up very fast and in some locations inside the engine can even boil. You can experience this by opening the coolant reservoir right after you stop the hot engine. You can see how the coolant level inside the reservoir raises up very fast until you put the cap back on. I think this is one reason the coolant is lost in the reservoir as with very hot engine it will boil and over flow from the reservoir when it reaches the pressure limit of the system.
While there are hot spots in the engine as you describe, the whole point of a pressurized system is to keep the coolant boiling point well above the hottest engine temperature the coolant should see. That coolant boiling point temperature is increased with pressure. The inverse is also true: When you open the cap and relieve pressure, you're also lowering the boiling point of the coolant, possibly to the point at which it will boil (depending on what ratio of glycol/water is in there). Another cause of the sudden apparent rise in the expansion tank level is all the rubber and otherwise expandable parts in the cooling system can now relax and push their content into the void you've created by relieving the pressure. Things expand when they get hot.
Or you may just have a blown head gasket. Or a bad water pump. Or your thermostat may be allowing the engine to get way too hot.
Anecdote: years ago I had a water pump quit turning on my Duramax diesel. That pump is gear driven off the crank, but the pump impeller is only pressed onto the driven shaft and that friction fit failed. Engine got hot, like close to the red zone hot. Being a moron, I popped the hood and took the cap off the expansion tank and the exact phenomenon you describe happened for the reasons I described: Under pressure, the coolant was liquid at that high temperature. Once I foolishly relieved the pressure, the coolant literally exploded into gas form and promptly blew all the coolant out of the engine through the expansion tank, straight up and into the hood where it went pretty much everywhere. I consider myself very lucky to have been fast enough to have not gotten a single drop on me.
Moral of the story? Keep your cap on.
Last edited by rapidoxidation; 07-29-2021 at 09:46 PM.
While there are hot spots in the engine as you describe, the whole point of a pressurized system is to keep the coolant boiling point well above the hottest engine temperature the coolant should see. That coolant boiling point temperature is increased with pressure. The inverse is also true: When you open the cap and relieve pressure, you're also lowering the boiling point of the coolant, possibly to the point at which it will boil (depending on what ratio of glycol/water is in there). Another cause of the sudden apparent rise in the expansion tank level is all the rubber and otherwise expandable parts in the cooling system can now relax and push their content into the void you've created by relieving the pressure. Things expand when they get hot.
Or you may just have a blown head gasket. Or a bad water pump. Or your thermostat may be allowing the engine to get way too hot.
Anecdote: years ago I had a water pump quit turning on my Duramax diesel. That pump is gear driven off the crank, but the pump impeller is only pressed onto the driven shaft and that friction fit failed. Engine got hot, like close to the red zone hot. Being a moron, I popped the hood and took the cap off the expansion tank and the exact phenomenon you describe happened for the reasons I described: Under pressure, the coolant was liquid at that high temperature. Once I foolishly relieved the pressure, the coolant literally exploded into gas form and promptly blew all the coolant out of the engine through the expansion tank, straight up and into the hood where it went pretty much everywhere. I consider myself very lucky to have been fast enough to have not gotten a single drop on me.
Moral of the story? Keep your cap on.
Yes, you can boil water at around 70C up in the high mountain...
I don't know what boiling point the coolant has but it probably is not that much higher than water. Stopped engine can have very hot points internally when it suddenly stops running and coolant flow stops. I would not be surprised some local boiling of the coolant actually takes place even when the cap is kept on. The point of my message was that there are very hot areas inside the engine when it stops running when that cooling fluid stops running. Boiling or not.
Coolant has boiling points listed on the bottle.
I remember it being in 115C range, but with modern system pressure, the red zone on the gauge is in 130C range.
Each time you refill cooling system bare in mind that closed thermostat will hold air bubble. You need to bring the engine to thermostat opening and recheck the level then.
Coolant has boiling points listed on the bottle.
I remember it being in 115C range, but with modern system pressure, the red zone on the gauge is in 130C range.
Each time you refill cooling system bare in mind that closed thermostat will hold air bubble. You need to bring the engine to thermostat opening and recheck the level then.
All thermostats that I have seen so far including the one I replaced on my E550 has a small weep hole in the flap so I don't think it can hold air bubbles.
All thermostats that I have seen so far including the one I replaced on my E550 has a small weep hole in the flap so I don't think it can hold air bubbles.
5 replies above you said that your coolant level, when overfilled went down after some time?
Aren't you contradicting yourself?
5 replies above you said that your coolant level, when overfilled went down after some time?
Aren't you contradicting yourself?
No I’m not and I don’t understand your question either based on my posts.
When I flushed the cooling system and re-filled I did it carefully letting the car run enough time with changing the heater settings in every way making sure there is no air pockets. I ended up filling the reservoir way up but left it there. Two days later I checked and level was down at the divider and I think this happens with hot engine sitting without circulating coolant so it over heats and boils in very hot areas inside the engine and this causes the expansion tank to over flow so the coolant level goes down when over heat situation is not present.
Letting a freshly flushed cooling system bleed by idling the engine isn't going to do it, no matter how careful one is. The pump needs to MOVE coolant to push all the air out, and that means RPMs. You burped the system by driving; that's why the level went down. If a cooling system boiled water every time it ran, don't you think you'd constantly be replacing lost coolant?
There is always lot of details, who will not make it to forum replies and quite often are overlooked.
I made the coolant refill easy job.
Most of my cars have 2 and some gallons cooling system capacity. I am not worry about deep freeze protection so don't need perfect 50% mix, So after good flush, I put 1 gallon of MB antifreeze, top it off with DW and take the car for a spin on low-traffic highway, becouse diesels will never reach 80C idling.
When I see my temperature gauge reaching 80C I pull over, take extra Distillate Water from the trunk and top it off again.
The MB reservoirs are design the way that at 80C coolant should reach the neck.
End of the story.
10-03-2019, 04:48 PM
