Cooling System Malfunction
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From: Louisville, KY
2023 EQE350 4MATIC, 2023 EQE 350 4MATIC SUV, 2015 E250 BlueTEC 4MATIC, 1995 E300 Diesel
That's pretty odd. Wonder if it's some sort of valve in the coolant loop that is used for heat pump, heat exchanger, etc. Though I'd assume that would be more catastrophic and would disable the vehicle. Whatever it is, I'm sure the car will do its best to stay within thermal limits and preserve your battery. Please keep us posted on what it was - did they tell you the part number? Would be interesting to look it up.
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Sounds familiar.. if only there was a big search box in the upper right hand corner of this site and I typed "cooling malfunction" into it maybe I could get a clue... but alas. :P
https://mbworld.org/forums/eqs-suv/8...rformance.html
https://mbworld.org/forums/eqs-suv/8...rformance.html
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C63
Sounds familiar.. if only there was a big search box in the upper right hand corner of this site and I typed "cooling malfunction" into it maybe I could get a clue... but alas. :P
https://mbworld.org/forums/eqs-suv/8...rformance.html
https://mbworld.org/forums/eqs-suv/8...rformance.html
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2025 Maserati Grecale Folgore and 2024 Jaguar F-PACE SVR
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C63
That's pretty odd. Wonder if it's some sort of valve in the coolant loop that is used for heat pump, heat exchanger, etc. Though I'd assume that would be more catastrophic and would disable the vehicle. Whatever it is, I'm sure the car will do its best to stay within thermal limits and preserve your battery. Please keep us posted on what it was - did they tell you the part number? Would be interesting to look it up.
I’ll report back. No feedback from the dealer on parts ordered yet.
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C63
Trending Topics
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From: Louisville, KY
2023 EQE350 4MATIC, 2023 EQE 350 4MATIC SUV, 2015 E250 BlueTEC 4MATIC, 1995 E300 Diesel
I wonder if it's the servo-controlled cooling slats on the front? I noticed when it was really cold and covered with ice, my sedan made a crunching noise as the slats opened and closed during the charge initiation. If that servo is stuck, it could reduce cooling during DCFC. Simple fix, but annoying of course.
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C63
I wonder if it's the servo-controlled cooling slats on the front? I noticed when it was really cold and covered with ice, my sedan made a crunching noise as the slats opened and closed during the charge initiation. If that servo is stuck, it could reduce cooling during DCFC. Simple fix, but annoying of course.
The slates don’t move if I put any pressure on them.
I have noticed no adverse affects just yet with the error. Hoping dealer “parts” come in soon.
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From: Louisville, KY
2023 EQE350 4MATIC, 2023 EQE 350 4MATIC SUV, 2015 E250 BlueTEC 4MATIC, 1995 E300 Diesel
When you plug in your level 2 EVSE (I'm sure it also does it with DCFC), head to the front quickly, you'll see the slats close and open. If your garage is quiet, you'll hear the servo as well. When we had snow and cold temps, some ice had formed on the mechanism after a car wash. The servo is quite strong though. Curious if yours is working as described. Do post the job notes when your repair is done!
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C63
When you plug in your level 2 EVSE (I'm sure it also does it with DCFC), head to the front quickly, you'll see the slats close and open. If your garage is quiet, you'll hear the servo as well. When we had snow and cold temps, some ice had formed on the mechanism after a car wash. The servo is quite strong though. Curious if yours is working as described. Do post the job notes when your repair is done!
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2023 EQE350 4MATIC, 2023 EQE 350 4MATIC SUV, 2015 E250 BlueTEC 4MATIC, 1995 E300 Diesel
Last edited by bytemaster0; Feb 4, 2024 at 06:27 PM.
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GLC300
Coolant Mafunction
My 2024 GLC300 did this today. Opened passenger door and engine fan came on and the coolant malfuction warning and engine light came on. I had not even driven it since day before. I drove it to an appointment and my car would not turn off. It said that function is not available. So, I left it running until it switched off on its own. Got back in a few hours later and just engine light was on. I had it towed to dealership. Only had it a few weeks. Waiting for answer Monday hopefully. Didn’t over heat and drove fine- strange
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C63
Yes covered under warranty. One of the cooling flaps in the front grill (bottom middle) got stuck in the open position so it threw that error. I think they changed the flaps and motor running the flaps.
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24 Mercedes C300 4matic
Are the cooling flaps unique to the electric vehicles? My conventional C300 put up the same dialog box. Currently at the dealer since Tuesday, no updates yet.
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From: Teaneck, NJ
2023 EQB300
Same thing with my EQB300. Replaced flaps. Changed out entire cooling system and cleared battery errors. Dealer actually wanted to replace battery but MB wouldn't approve. But car has actually gone 3 months without a repair so that is a record for this piece of trash car.
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Perhaps the electrically controlled flaps is part of MB's goal of being more aerodynamic, so it shuts it off when cooling isn't needed? Failing grille flaps is not a new thing in the automotive industry so in MB's defense, bmw had failing grille flaps too.
https://g05.bimmerpost.com/forums/sh....php?t=2044553
https://g20.bimmerpost.com/forums/sh....php?t=2085511
https://g05.bimmerpost.com/forums/sh....php?t=2044553
https://g20.bimmerpost.com/forums/sh....php?t=2085511
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From: Louisville, KY
2023 EQE350 4MATIC, 2023 EQE 350 4MATIC SUV, 2015 E250 BlueTEC 4MATIC, 1995 E300 Diesel
The flaps aren't just for aerodynamics - there are times you don't want to cool the battery and drivetrain in colder temperatures, so they should remain closed. W205 C-class from 2015 featured them in combustion cars, and of course EVs have it as well.
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Are we talking about the same flaps, there are none of those grille flaps on the W205 as far as what I seen.
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From: Louisville, KY
2023 EQE350 4MATIC, 2023 EQE 350 4MATIC SUV, 2015 E250 BlueTEC 4MATIC, 1995 E300 Diesel
MBWorld God!
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MBWorld Fanatic!
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From: Louisville, KY
2023 EQE350 4MATIC, 2023 EQE 350 4MATIC SUV, 2015 E250 BlueTEC 4MATIC, 1995 E300 Diesel
