Yesterday I was «exploring’ the MBUX system and screen and I’m thinking I must have turned something off. Today the heater is not producing any heat. The fan, controls, all seem to be working fine but zero heat. Any ideas out there?
seřadit
Všechno je to o kolech!
Same issue. Comes and goes. I’ve read it’s a ‘software’update. I have an appt with dealer in a few cold weeks.
any others have this issue?
hilld
Známý člen
I have an appt at the dealer tomorrow to hopefully address this.
seřadit
Všechno je to o kolech!
Please let us know how it goes
hilld
Známý člen
The software was updated and a quick test showed that the air is now coming out where it is supposed to. I select the vents next to the MBUX and air comes out of those vents now. That wasn’t the case before.
seřadit
Všechno je to o kolech!
were you having an issue with NO heat? Did the software issue change anything. Thanks for the follow up!
Mrshakedown
Aktivní člen
Mine does this time to time. Dealer tells me it’s me..
seřadit
Všechno je to o kolech!
As in you don’t know how to operate the heater controls @Mrshakedown?
hilld
Známý člen
were you having an issue with NO heat? Did the software issue change anything. Thanks for the follow up!
I had intermittent no heat and the air not coming out of the correct vents. Most of the time the air came out of the defrost vents, even if other were selected. It is too early to tell if this fixed it for good.
Mrshakedown
Aktivní člen
I think that’s what they suggest.
MAYBE THEY ARE RIGHT.
Im pretty sure it’s not me as it happens once every blue moon.
As in you don’t know how to operate the heater controls @Mrshakedown?
seřadit
Všechno je to o kolech!
Hmmmm, i have air from all of my vents but no heat when i turn the heat up. this has happened once in mid September,then it came back for a few weeks and now the heat is MIA again.
Mrshakedown
Aktivní člen
That sounds exactly like what happens to me…
Hmmmm, i have air from all of my vents but no heat when i turn the heat up. this has happened once in mid September,then it came back for a few weeks and now the heat is MIA again.
hilld
Známý člen
The software controls all the blend doors, not only air flow direction but also heat. I would highly recommend going to your dealer and get the software updated, especially since most of the VS30’s are probably still under the 3yr warranty.
If you want to confirm that the software is at fault, the next time you don’t have heat, pull over, open the hood and touch the hoses that go to your heater core by the firewall. If they are hot and you don’t have heat, it is the blend door in your dash, if the hoses are not hot, most likely the H-valve is to blame, but if I were a betting man, I would suspect your software needing to be updated.
Full disclosure, I have the fully automatic HVAC system, but I am pretty certain this applies to the non Auto systems.
Mendeleev34
Aktivní člen
Now I think I am having the same issue. Never noticed it before since we hardly use the heat in the bay area. but today I set the system on Hi and it was cold air blowing out of the vents next to the MBUX. Later in the day I turned on the front defrost while the rest of the system was OFF and both the defrost and the front vents were blowing super hot air. Not sure how that could happen. Switched on the heater to Hi and setting 5 and hot air still blew from the front vents. Not looking forward to this happening up in the Tahoe area.
hdaniels
Aktivní člen
Happen to me as well, but it fixed itself for now. Definitely can see a trend here.
djsincla
Aktivní člen
Logged on today for this exact issue. Van heat stopped this evening after a stop. I was going to ask if anyone had a clue what fuses needed to be checked. Looks like a trip to MB next week
800summit
Nový člen
h
Happened to me, after this happened, I turned the van off for 10 min, came back out and it started working again.
This will not go to well, since I live in Alaska
Valeria2019
Člen
Update on mine. After the Van was off for about an hour, I restarted it and the heat began working again normally. Round trip out to Utah and back to Oregon, no issues yet. But I will speak to the shop later next week about a software update.
djsincla
Aktivní člen
Mine is at the dealer now. It will be interesting to see what they end up doing to fix the issue.
SockeyeRed
Člen
My understanding this is fairly common. I’ve had intermittent issues with no heat and only blowing cold air as well as no air flow to the wind screen.
My understanding is the cause is usually a software issue and or defective stepper motor. The stepper motor is software controlled so it’s also possible MB techs misidentify the issue as mechanical with the stepper motor when in fact the cause is software.
The heater in Mercedes-Benz C-Class ensures comfortable temperature in the passenger compartment when the weather is chilly. There are many reasons for poor heating performance in C-Class, which are explained in this article.
The heater may stop working in Mercedes-Benz C-Class due to low coolant level or air in the cooling system, clogged heater core, bad thermostat, faulty blend door actuator, bad water pump, dirty cabin air filter, bad blower motor, or HVAC control unit malfunction.
1. Nízká hladina chladicí kapaliny nebo vzduchu v chladicím systému
Low coolant level or air in the cooling system can cause the heater to stop working properly in C-Class. If the cooling system is not full and bled properly, the water pump will not be able to push the coolant around the system efficiently.
The heating system in C-Class uses hot coolant or antifreeze from the engine block to heat the interior of the vehicle. The hot coolant is pumped through the heater core located behind the dashboard. When you turn on the heating, air gets blown through the heater core, warming the air in the cabin.
Pokud je uvnitř jádra ohřívače zachycený vzduch, chladicí kapalina jím nebude moci správně proudit. Vzhledem k tomu, že topné jádro je obvykle o něco výše, vzduch se v něm bude hromadit jako první. Naplněním a řádným odvzdušněním systému by se mělo teplo vrátit.
Zvuk šplouchání vody
Nízká hladina chladicí kapaliny nebo vzduchu v jádru topení může někdy způsobit cvaknutí zpoza palubní desky, když je motor v chodu. Zvuk je nejvýraznější hned po nastartování vozidla.
Zkontrolujte hladinu chladicí kapaliny
Checking coolant level in C-Class is a fairly some job. You just have to locate the coolant overflow reservoir and inspect the level of coolant in it. If the coolant level is low, open the cap and pour some coolant into the tank until it is between minimum and maximum mark.
Doporučené video
Jak zkontrolovat, zda není ucpané jádro topení
You don’t have to remove the heater core in your C-Class to check if it is clogged. Locate two rubber hoses that connect to the heater core through the firewall area. Feel both the rubber lines going in and out of the heater core after the engine has warmed up. Both should be hot. If one is hot and the other is cold, you have a plugged heater core.
Propláchněte topné jádro
Before you consider replacing the heater core in your C-Class, it is recommended to flush the existing heater core. Flushing is done by pushing water through the outlet hose of the heater core and draining the gunk from the inlet hose. There are flush kits available in the market that can help you do the job yourself.
3. Špatný termostat
Thermostat is a part of the cooling system in Mercedes-Benz C-Class which ensures that the engine reaches its optimal operating temperature as quickly as possible and maintain it under all operating conditions.
Termostat je zaseknutý otevřený
When you start your C-Class when the engine is cold, the thermostat cuts off flow of coolant through the radiator in order to quickly reach the optimal engine operating temperature. But if the thermostat has developed a defect and is stuck to open position, the coolant will continuously flow through the radiator and the engine may take a long time to reach its optimal operating temperature.
Ohřívač fouká horký vzduch dlouho
Since the heating system in C-Class relies on the hot coolant from the engine to heat the interior, the heater will blow cold air until the engine reaches its normal operating temperature. But if the weather is too cold, the engine may never reach its optimal operating temperature with a stuck open thermostat. Your vehicle may also consume more fuel than normal.
5. Špatná vodní pumpa
The water pump is the heart of the cooling system in C-Class responsible for pumping coolant throughout the system and cooling the engine. If the water pump has worn out and the coolant is not being circulated as effectively as it used to, it can cause the heater to stop working properly because there’s less coolant available to transfer heat between the engine and the heater core.
Vodní čerpadla obvykle vydrží více než 100,000 XNUMX mil, ale mohou kdykoli selhat. Špatné vodní čerpadlo způsobí nejen špatné zahřívání, ale také může mít za následek poškození motoru v důsledku přehřátí. Proto je důležité diagnostikovat vadné vodní čerpadlo v raných fázích, abyste se vyhnuli pozdějším nákladným opravám.
6. Vadný akční člen míchacích dveří
Blend door actuator plays a role in controlling the temperature inside your C-Class. If the blend door actuator fails to fully open the blend door towards the heater core, it will result in poor heating performance.
Nejčastějším příznakem vadného pohonu dveří u Mercedes-Benz třídy C je slabé cvaknutí (nebo jiný neobvyklý zvuk), které opakovaně vychází zpod palubní desky. Zvuk bude nejvýraznější na několik sekund, když zapnete klimatizaci nebo upravíte teplotu.
Příznak: zvuk klepání
Klepání zpoza palubní desky může být indikátorem špatného ovládání dveří ve vaší třídě C. Zvuk je něco jako lehké klepání na dveře a obvykle se to stane, když zapnete/vypnete klimatizaci nebo nastartujete motor.
There is no fixed time for replacing the cabin air filter, but most manufacturers recommend a change after 10,000-20,000 miles. If you drive your vehicle in dusty or polluted environment, the filter can get dirty much sooner than manufacturer’s recommendation. Additionally, if you drive your C-Class with AC system set to fresh outside air most of the time, your cabin air filter will get dirty much sooner as compared to air recirculation mode.
Pro optimální výkon vyměňte filtr na začátku každé zimy
Obecně se doporučuje vyměnit kabinový vzduchový filtr každý rok na začátku zimní sezóny. Jarní a letní období je pro kabinový vzduchový filtr náročné kvůli pylu a broukům a na podzim se může ucpat zbytky listů. To vám dává nový start do zimy, zlepšuje výkon rozmrazování a snižuje pravděpodobnost růstu plísní nebo plísní.
Doporučené video
Když se motor ventilátoru pokazí, obvykle to při provozu vydává neobvyklé zvuky a cestující mohou cítit snížené proudění vzduchu z ventilačních otvorů. Mějte na paměti, že snížený průtok vzduchu nemusí vždy znamenat problém s motorem ventilátoru, protože k němu může dojít také v důsledku ucpaného vzduchového filtru kabiny, špinavého výparníku nebo špatného režimu ovladače dveří. Při diagnostice špatného proudění vzduchu je tedy nutné zkontrolovat všechny.
9. Motor mrtvého ventilátoru (žádné proudění vzduchu)
If there is no air flow from the air vents in the dashboard when you turn on the heater in your Mercedes-Benz C-Class, it means the problem is related to the fan or blower motor function.
The most common causes for blower motor not working in Mercedes-Benz C-Class are blown fuse, bad relay, resistor or control module malfunction, and faulty blower motor. However, a bad electrical connector or broken wire, or a defect in the climate control unit can also cause the blower motor to stop working.
10. Znečištěný výparník
Dirty evaporator can cause weak airflow and reduce the heating performance in C-Class. Although, the evaporator coil is a component of the cooling function of the air-conditioning system, but the air always first passes through the evaporator and then flows over the heater core.
Vzduchový filtr kabiny zachytí většinu nečistot nebo jiných polétavých částic, ale některé částice unikají a mohou se usadit na výparníku. Časem se tyto částice usazují na žebrech a blokují proudění vzduchu přes výparník, což způsobuje snížené proudění vzduchu v kabině a špatné vytápění nebo chlazení.
Funkce výparníku v režimu topení
Když je ohřívač zapnutý a klimatizace vypnutá, kompresor se nezapne a výparník se neochlazuje. Když stisknete tlačítko AC v režimu topení, kompresor se zapne a výparník ochladí a vysuší vzduch předtím, než vstoupí do jádra topení. Tento režim je užitečný pro odstranění mlhy z oken.
11. Vadný modul HVAC
Climate control module is the brain of the air-conditioning system in your Mercedes-Benz C-Class, responsible for controlling all the components in the system. In rare cases, a fault in the climate control unit can cause the heater to stop functioning. This would require a scan tool to confirm correct operation.
12. Profouknuté těsnění hlavy
The head gasket is responsible for providing the seal between the engine block and cylinder heads. Its purpose is to seal the combustion gases within the cylinders and to avoid coolant or engine oil leaking into the cylinders. Leaks in the head gasket can cause all sorts of problems in your C-Class including poor heater performance. This is mostly common in older vehicles.
Unikající výfukové plyny
Prasklé těsnění hlavy může způsobit, že výfukové plyny z motoru proniknou do chladicího systému a ucpou jádro topení. Vyčištění vzduchu z jádra topení nepomůže, dokud nebude vyměněno těsnění hlavy.
Únik chladicí kapaliny
A blown head gasket can cause coolant to leak into the combustion chambers and burn off. If your C-Class is losing coolant, that means there is a leak somewhere or it is getting burned up inside the engine.
Jak zkontrolovat, zda u třídy C netěsní těsnění hlavy?
Nemusíte chodit do servisu, abyste zkontrolovali, zda ve vaší třídě C netěsní těsnění hlavy. Na trhu jsou dostupné testovací sady, ve kterých stačí vložit hadičku naplněnou barevnou kapalinou do chladiče (na místo uzávěru chladiče) a poté nastartovat motor. Pokud kapalina změní barvu, pak je netěsnost v těsnění hlavy.
Zapněte režim recirkulace vzduchu
When the outside temperature drops too low, the heating performance may be reduced in C-Class if the air conditioning system is set to outside air. To improve heating efficiency, it is recommended to switch on air recirculation mode. Don’t worry, there is no risk of suffocation, as the air recirculation mode still allows up to approximately 10 percent of the air coming from the air vents to be fresh air from the outside.
Proč investovat do čističky vzduchu?
There are many reasons why the heater in your Mercedes-Benz C-Class is not working properly. When looking for the reason, you should start with the most obvious causes: low coolant level or air in the cooling system, and clogged heater core.
V každém případě je vhodné, aby laici navštívili dílnu. Profesionální mechanik vám rychle diagnostikuje problém s topením.
