Check coolant level when heating
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From: Houston, TX
2019 E450 Sedan 4Matic
Check coolant level when heating
Ok,
I keep getting this check coolant level message whenever I turn on the heater. I check the engine temp and it never passes 90oC and I get the message soon after I start the car and put on the heater ~50oC engine temp. Anyone know the problem?
I keep getting this check coolant level message whenever I turn on the heater. I check the engine temp and it never passes 90oC and I get the message soon after I start the car and put on the heater ~50oC engine temp. Anyone know the problem?
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From: Houston, TX
2019 E450 Sedan 4Matic
Actually I haven't lol but I thought it was some wierd messup since my engine temp is low. I did buy some Zerex G-05 today incase the coolant is indeed low. Sorry I'm such a noob.
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
+1 - Benz coolant is trick stuff & a lot revolves around what is not in it. Benz ban many constituents for good reason as they do damage. Open a Benz engine at a very high mileage if correct coolant concentrations have been maintained and it will be perfect in the water jackets etc. No corrosion & no scale build up. Shiney aluminium.
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Because your “coolant check level !” warning is only illuminated when the heater is on, it is possible that the additional fluid directed to the heater core is displacing just enough antifreeze from the reservoir to trip the warning sensor. There is a separate electric pump (on most models) that is activated to aid circulation when heat is selected on the HVAC control.
If the warning is not spurious, then it is low on antifreeze. It is easy enough to top up, but must be done only with the engine cold to avoid the very real possibility of being scalded. Remove the reservoir's cap. Start the engine and activate the heater. Fill the reservoir to just below the bottom of its neck. Squeeze the upper radiator hose several times to help expel any air pockets that may be present. Refill the reservoir as required. As the antifreeze begins to warm (after a couple of minutes), it will expand. Be prepared to reinstall the cap promptly. It may take a few cold engine refill attempts to ensure that all the air has been evacuated from the system.
The warning begs the question of where did the antifreeze go? Some very slight evaporation is to be considered normal, but if there is an internal or external leak, it should be tended to promptly so that even more expensive repairs can be averted.
If the warning is not spurious, then it is low on antifreeze. It is easy enough to top up, but must be done only with the engine cold to avoid the very real possibility of being scalded. Remove the reservoir's cap. Start the engine and activate the heater. Fill the reservoir to just below the bottom of its neck. Squeeze the upper radiator hose several times to help expel any air pockets that may be present. Refill the reservoir as required. As the antifreeze begins to warm (after a couple of minutes), it will expand. Be prepared to reinstall the cap promptly. It may take a few cold engine refill attempts to ensure that all the air has been evacuated from the system.
The warning begs the question of where did the antifreeze go? Some very slight evaporation is to be considered normal, but if there is an internal or external leak, it should be tended to promptly so that even more expensive repairs can be averted.
Last edited by splinter; Nov 22, 2008 at 01:52 AM. Reason: typo
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03 g35 coupe...........02 c32 Sold
Because your “coolant check level !” warning is only illuminated when the heater is on, it is possible that the additional fluid directed to the heater core is displacing just enough antifreeze from the reservoir to trip the warning sensor. There is a separate electric pump (on most models) that is activated to aid circulation when heat is selected on the HVAC control.
If the warning is not spurious, then it is low on antifreeze. It is easy enough to top up, but must be done only with the engine cold to avoid the very real possibility of being scalded. Remove the reservoirs’ cap. Start the engine and activate the heater. Fill the reservoir to just below the bottom of its neck. Squeeze the upper radiator hose several times to help expel any air pockets that may be present. Refill the reservoir as required. As the antifreeze begins to warm (after a couple of minutes), it will expand. Be prepared to reinstall the cap promptly. It may take a few cold engine refill attempts to ensure that all the air has been evacuated from the system.
The warning begs the question of where did the antifreeze go? Some very slight evaporation is to be considered normal, but if there is an internal or external leak, it should be tended to promptly so that even more expensive repairs can be averted.
If the warning is not spurious, then it is low on antifreeze. It is easy enough to top up, but must be done only with the engine cold to avoid the very real possibility of being scalded. Remove the reservoirs’ cap. Start the engine and activate the heater. Fill the reservoir to just below the bottom of its neck. Squeeze the upper radiator hose several times to help expel any air pockets that may be present. Refill the reservoir as required. As the antifreeze begins to warm (after a couple of minutes), it will expand. Be prepared to reinstall the cap promptly. It may take a few cold engine refill attempts to ensure that all the air has been evacuated from the system.
The warning begs the question of where did the antifreeze go? Some very slight evaporation is to be considered normal, but if there is an internal or external leak, it should be tended to promptly so that even more expensive repairs can be averted.
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..what's it's MB Service Products page listing? XXX.YY?..
Page 16 in this Approved Service Products booklet stolen from another member…
Last edited by splinter; Oct 6, 2010 at 07:02 AM.
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2005 C230K sport
the wife's 05 230K is exhibiting the same message. i haven't checked to see if the message goes away when the heater is off but i will in short order. the fluid level in the tank was ~halfway last time i looked at it. i'm wondering if the low coolant is indeed the problem, where did it go? no leaks on the ground whatsoever and no white smoke out the tailpipe as if it had a headgasket problem. except for the message, the car runs great. additionally, i'm not up to speed on the specifications and numbers for zerex and MB fluid. is MB fluid indeed re-branded zerex or not and is it safe to use?
Last edited by Cholleman; Nov 23, 2008 at 04:18 PM.
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
Thanks John - I'll look up the 325.0 micro fische at the office during the week & see if the Zerex material is listed. I know what the OE material is. Just need to see if Zerex is a rebrand of that material.
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Thought you were retired!
During the ill-fated marriage between Mercedes-Benz and Chrysler, the lesser of the two stipulated any HOAT G-05 antifreeze as being acceptable in the M112s they sourced for their Crossfire & SRT-6 models. We all know how well that relationship ended.
It could be that less costly antifreeze for us was an unintended offspring. :-)
During the ill-fated marriage between Mercedes-Benz and Chrysler, the lesser of the two stipulated any HOAT G-05 antifreeze as being acceptable in the M112s they sourced for their Crossfire & SRT-6 models. We all know how well that relationship ended.
It could be that less costly antifreeze for us was an unintended offspring. :-)
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Ok follow up, I don't know how much to fill it with since there is no fill line but I poured about 600mL of 50/50 in the reservoir. It would take about 200mL more to fill to the neck but I decided not to. Got no message, but then again, I haven't turned the heater on when it was cold outside (did a heater test a bit earlier but its much warmer now than what it was when I used to get those messages. Anyways, I hope there is no bigger problem like a leak. Thanks for contributing.
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Ok follow up, I don't know how much to fill it with since there is no fill line but I poured about 600mL of 50/50 in the reservoir. It would take about 200mL more to fill to the neck but I decided not to. Got no message, but then again, I haven't turned the heater on when it was cold outside (did a heater test a bit earlier but its much warmer now than what it was when I used to get those messages. Anyways, I hope there is no bigger problem like a leak. Thanks for contributing.
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
Thought you were retired!
During the ill-fated marriage between Mercedes-Benz and Chrysler, the lesser of the two stipulated any HOAT G-05 antifreeze as being acceptable in the M112s they sourced for their Crossfire & SRT-6 models. We all know how well that relationship ended.
It could be that less costly antifreeze for us was an unintended offspring. :-)
During the ill-fated marriage between Mercedes-Benz and Chrysler, the lesser of the two stipulated any HOAT G-05 antifreeze as being acceptable in the M112s they sourced for their Crossfire & SRT-6 models. We all know how well that relationship ended.
It could be that less costly antifreeze for us was an unintended offspring. :-)
Regarding retirement - just back from a holiday in Thailand but now it's flat out consulting to 31 December. Realigning & divesting of company assets all over the place. Ah! well - The unexpected income is good.
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Broken Piece For Coolant
This piece broke part # 0039970689 do you guys know where I can find it? It's a $7 part and the dealer says they can't get it for a week...It broke off the tube that goes from the coolant to the engine. And i need to get my car back up and running as soon as possible.
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What amount is considered "normal"? There is no MB publication that I have ever seen that has stated what amount is normal, and what amount you should be taking your car to the dealer.
The day my car arrived at the dealer, it was ~1/8 from the black top when cold. Now it is about a little over 1" from the top when cold. Never a drop added, and I have owned the car exactly 1 year and 8 months.
The day my car arrived at the dealer, it was ~1/8 from the black top when cold. Now it is about a little over 1" from the top when cold. Never a drop added, and I have owned the car exactly 1 year and 8 months.
