I did a coolant flush and I'm not getting any heat. I have been talking to the Lex on this thread about the problem. He has been very helpful, but i would like to know how to test this before i go down the replacing part lane.

Heater core seems to be getting the temp and everything seems to be checking out but I'm still not getting heat coming out of the vents.

I used a coolant evacuation tool. and filled the system completely with no air bubbles. I was getting heat before and now i have non. Lex suggested to change the heater core sensor and the Servo motor.

All the hoses and coolant path have all the same or the temps look about right.

What does the Heater core temperature sensor do?

I have the Bentley book but there is not mention of the Electric Auxillary heater.

here are pictures.



Heater core Temp




Inlet




Outlet




Vent Temp




No bubbles




Lex suggested to replace 3 and/or 6. I would like to test this before spending money. does anyone know how to measure to make sure this sensor is no good.

 

When you hear up the car from stone cold, with the expansion bottle open, do you notice when the thermostat opens? As in...coolant suddenly cascades out of the bottle and bleeder screw? Im trying to figure out if maybe your thermostat is starting to fail or not.

 

Just read that the electrical auxiliary heater is only fitted in diesel engines.

Electrical diagrams for cars WITH and withOUT Integrated Heating/Cooling should be in the back of Bentley. Let me know if not.

 

Where on earth did you get a brass bleed screw? Mines plastic and recently replaced.

The way that thermostat housing and heater core is designed, the heater core should get to the same temperature as your engine coolant because the coolant always flows though the radiator core. I know this all to well, those pipes were blowing how air on to my foot while wearing sandals traveling to the beach! There even a service bulletins for it to install insulation on the two heater core pipes.

You must have air trapped in your cooling system, I have seen it a thousand times here on NAM. If your having issues bleeding the air out, get it done by someone who can pressurize the entire cooling system. Another suggestion is squeeze the lower and upper radiator hoses to squeeze the air out.

 

I used a Coolant evaluation kit this time, but im hoping you guys are right winter is coming loo. Ill try massaging the hoses and see what happens.

 

HaveATank, if I remember from our previous discussion, you had heat before the coolant flush yes? If so, then really, what are the chances the blender motor took a **** at the same time? I agree with Systemlord...the most likely culprit is the most common culprit. Air in the lines somewhere. That's a bummer considering you put the system under vacuum and drew the coolant into the vacuum and still, there is an air pocket.

Make sure and race the engine a little with the bleeder and cap off.

What I'm not sure of is what the max heat temps you should be getting. Maybe 120 -150F? Not even sure. Never considered it before now.

 

I know man. this is driving me nuts. I'm just had the thought that maybe something is going not completely gone yet but something is malfunctioning. I have been using my other car but as soon as i get a chance I'm going to try to massaging the hoses and at the same time leaving the tank cap off as well as the bleeder. It not super cold at the moment but hope this heat returns soon lol.

What do you mean by race? dont know if this is a typo or you are telling me to run the car fast.

 

...as in raise the rpms while the cap and screw are open, and heater on the HI position.Get that coolant pump spinning fast.

Feel me?

 

K figure it was a typo.

Im going to try all this today. Hoping you guys are right. But damn this car is crazy. Cant believe something so simple as this is such a pain.

 

This is an example why I would have it done, don't want the headache of certain jobs that take up my valuable time.

 

I understand what you mean, but to be honest i dont think the stealership or an independent mechanic would have done any better and if it was done at the stealership it would have been throwing parts at it, something i can do my self and only the stealership mechanic and god would know if they F$!#ed up or not and more then likely i would have to pay for his mistake. This is not a hard job at all. I mean it super simple, but again this over engineering of this euro cars is incredible. Something simple made complicated for no good reason. Lol.

 

I think it's really stupid not to have a radiator cap (metal not plastic! ) because if your running low on coolant and you try to add some coolant, you can't without coolant gushing out so your kind of screwed if it means your engines going to overheat and possibly have a warped head! Dumb German engineering, dumb and dummer! No more cars from that part of the world!

 

So never got around to do what you guys suggested, but guess what started to work today. You guess it heat. So i tested by switching the temp wheel to cold. And guess what waa blowing nothing but hot hot air. Good for now i guess since we are going into winter, but im going to assume to blender servo is no good. Or the switch is no good.

So do you guys have any way to test. Which is the actual bad boy?

 

I would guess that the trapped air finally made it to the coolant over flow bottle. I would check the coolant level..

 

If your heater core is reading 161F then there's air trapped in there plain and simple and the solution is simple, it's time for you to quit fiddling () with it and have the coolant system professionally done because it isn't working out for you. Everyone is telling you the exact same thing, I'm sorry this is causing so much grief. These German cars can be difficult to work on, trust me there's some things about these cars that make me scratch my head in regards to most of the engineering.

All my other cars had the cam sprockets keyed into the camshafts (like the HPFP, vacuum pump) with actually timing marks/arrows to align with the timing chain, you didn't have to lock the camshafts and crankshaft. Anyway the clue is staring at you in one of your pictures, the one with the measurement of 161F at the heater core. That's not right, it should read the same as your coolant gauge.

Nobody said go to the dealership, I find them less than honest and their prices on parts and labor are unreal considering the low build quality! I wouldn't mind spending Mini dealership prices on parts and labor if the Mini's were super reliable and hit 200,000 miles without needing to replace HPFP, timing chains, timing chain tensioners multiple times in the cars lifespan (under 100,000 miles) which isn't very high to begin with!

Best regards,
Systemlord.

 

Ha Ha. I had a 1960 Austin Mini 850 with the optional heater. There was a 5 by 7 inch radiator under the dash with two rubber tubes thru the firewall connected to the cooling system. If you wanted heat you opened the bonnet and flipped a brass valve open. Behind the radiator was a tiny fan switched on the dash. No fresh air, recirc within the cabin.

 

You know the R56 doesn't have a temp gauge right? The only way to know your temp is to hook something up to the obd 2 port. Also there really isn't much anyone else with out knowledge of what kind of readings voltage or resistant of the components which are thought to be defective is suppose to be or a dealer computer which may have the ability to run a test on this components via OBD or maybe by plugging an adapter to the Climate control module/servo motor can do.

It apparent to me that i not a matter of air in the system at this point. It something else malfunctioning. Also if you look at post 13, where i said that I'm getting heat, but it seems like it the blender servo or the actual Climate control switch doesn't work or maybe the heater core temperature is malfunctioning. Which is why I'm trying to find out what is the purpose of the heater core temp. is it simply to cut coolant flow to the heater core so it doesn't over hear or does it service other purpose.

When i start the car in the morning I'm able to get heat and able to switch between hot and cold for a short time (like 30 seconds and you can feel the temp changing depending in which direction the temp wheel is turned to) and then it seems like it just gets suck in either hot or cold. it doesn't blend at all (so it either hot or cold), So i don't know if it the switch that stops sending a signal or the servo motor which stops responding. I don't know which of the two is defective or if both are I figure it not some kind of fuse because it does it job for a short time.

161f+ is not that hot for a heater core at all. this is normal. Don't know your experience with cars, but there is nothing to be concerned about the temp. This doesn't indicate theirs air or not. it actually indicates that the coolant is flowing properly since everything matches give or take 10+/- degrees.

Here is a picture of what is coming out of the vent now.

 

Found a Servo motor for $25, So i just went and bought it, I just cant seem to find the Climate control switch. It looks like it all together with the window up/down Fog light front and rear and lock switch. I have rear and front fog lights and can't seem to find one that has it all. I don't have heated seats so that does bother me. Any help?

 

Can i use this and add some way some how the rear/front fog light switch from my Climate control?

 

Well, seems you're on the right path hommie. Servo for the blender door seems to be acting up.

The servo is inside that unit you're showing a picture of? Can you take a picture of the back of that unit?

I wish I could be of help with your last question. I checked and checked ALLDATA and couldnt find anything on this. Whatever I posted in the other thread on this subject represents the best I can find. Not at all helpful.

They do mention something in RELAYS AND MODULES which is related but not helpful:

Vehicle » Heating and Air Conditioning » Relays and Modules - HVAC » Control Module HVAC » Diagrams » Diagram Information and Instructions » Signal Glossary » Signal Names With S; and then STEP1_MK Activation, mixing-flap motor, and on and on and on...a very long list.

Are those the associated code names used BMW software? I dont know.

 

Here is the pictures i got from listings on ebay. I need the motor, they are both the same. I already ordered one. Still trying to figure out what is the full purpose of the heater core temp sensor beside the obvious of monitoring the heater core so it doesnt get hot. Wondering if i would actually need one. Wouldn't want to do this job several time, so at this moment I'm juat going to throw the logical parts at it.

Thanks for the reply and the help lex










The bottom is the blender motor.

 

Jesus...its all one integrated unit.

Ok here is some reading for you which may answer your question on the temp sensor relating to the automatic HVAC:

Integrated Automatic Heating/air Conditioning (IHKA)

IHKA (integrated automatic heating / air conditioning system)
This functional description covers the integrated automatic heating and air conditioning system. The IHKA is a heating and air conditioning system regulated on the on air side. The interior temperature is picked up by two independent temperature sensors. The sunlight level is picked up by the solar sensor. The IHKA is used to adapt the in-car climate to the individual needs of the passengers. Information is exchanged between the vehicle components involved via the body CAN data bus.
There are no differences for left-hand drive and right-hand drive vehicles. The control unit with operating unit is always fitted in the same position in the vehicle.
The control unit has the following functions (see also individual functional descriptions):
Temperature control
Air distribution
Air flow control
Automatic recirculated air control / recirculated air mode
Heated windscreen and rear window
Brief description of components

Control unit with operating unit
The IHKA control unit records the signals of the IHKA components and controls/regulates the heating and air conditioning process. The control unit is at the same time the operating unit of the IHKA.

The IHKA control unit also contains the bank of switches. The bank of switches can be used to operate the seat heating (if installed), the heated windscreen and heated rear window, as well as the electrical power windows. The center lock button as well as the switches for the fog lamps and rear fog lamp are also built in.

Heater/air conditioner
The IHKA heater/air conditioner is fitted underneath the instrument cluster in the centre, at the front bulkhead. The heater/air conditioner performs the tasks:
Generation and regulation of air quantity
Air distribution, air mixture (stratification) and air dehumidification
Transfer of refrigerating output generated by the cooling circuit
Transfer of heat output delivered by the refrigerant circuit

The heater/air conditioner is composed of the following components:
Evaporator The evaporator plates are cooled by the coolant evaporating inside. The air-mass flow supplied by the blower is guided over the cool evaporator plates. The air is cooled and dried and guided into the vehicle interior.
Heat exchanger for heating system and heating system heat exchanger sensor The heating system heat exchanger sensor is fitted directly behind the heat exchanger for the heating system. The heating system heat exchanger sensor measures the temperature of the heat exchanger for the heating system.
Flaps with drive and mechanical system The flap motors are connected directly to the IHKA control unit. Three flap motors are fitted in the IHKA. The flaps serve to distribute the air and to mix hot and cold air.
Fresh air recirculated-air flap: the amount of clean air drawn in by the blower is regulated with this flap.
Air distribution flap: The air distribution flap mechanical system mechanically adjusts the air distribution flaps. The air distribution flap mechanical system is driven by the air distribution flap motor. The air distribution flap motor has the task of setting the air distribution by means of a cam disk. The air distribution flap motor has no detection of the actual position. In order to ensure unique positioning of the cam disk nonetheless, there are 2 cams of different widths on the cam disk. The micro-switch signals to the IHKA control unit that the cams have been passed over. This mechanism achieves reliable and rapid positioning of the cam disk.
Temperature mixing flap: The air-mass flow is guided through the evaporator. The air-mass flow is cooled and dried in the evaporator (when the air conditioning system is switched on). Subsequently, the temperature mixing flap guides the air-mass flow (depending on the set desired temperature value in the IHKA controls) fully or partially over the heat exchanger for the heating system and the electrical auxiliary heater (diesel engine).

Blower with blower output stage The blower creates the necessary air-mass flow. The blower is fitted after the fresh air recirculated-air flap in the heater/air conditioning system (pressing blower arrangement). The blower output stage is mounted directly at the housing of the blower motor. The blower output stage is activated by the IHKA control unit with a pulse-width modulated signal (PWM signal). The blower output stage is not diagnosis-capable.
Electrical auxiliary heater The electrical auxiliary heater based on the PTC principle (positive temperature coefficient) is fitted in the heater/air conditioner. The electrical auxiliary heater directly heats up the air to adjust the temperature of the vehicle interior. The electrical auxiliary heater is only fitted in diesel engines.
Radiator fan
The radiator fan and the engine cooling are also required for cooling the condenser. The radiator fan is activated by the Digital Engine Electronics (DME).
Signal path:
IHKA control unit -> K-CAN -> Junction box electronics -> PT-CAN -> DME -> Radiator fan

A/C compressor
The air-conditioning compressor compresses the refrigerant taken in by the evaporator. The refrigerant is pressed towards the condenser. The air-conditioning compressor is switched by the compressor coupling. Activation is initiated by the IHKA control unit.

Condenser with integrated drier flask
In the condenser, gaseous refrigerant is converted into liquid refrigerant. In the integrated downstream drier flask, any water present in the refrigerant circuit is bound. The drier insert can be replaced.

Sensors
Internal temperature sensor The internal temperature sensor is built into the IHKA control unit. The internal temperature sensor measures the temperature in the control unit. This measured temperature is used by an integrated mathematical model to calculate the value for the interior temperature.
The internal temperature sensor is not force-ventilated. This means that no internal temperature sensor fan is fitted in the IHKA control unit.

Solar sensor The solar sensor consists of a photo diode. The solar sensor picks up external light or heat sources (e.g. sunlight). The solar sensor provides the IHKA control unit with an analog signal depending the intensity of the sunlight in each case.
Adaptation to the sunlight is only active in the automatic program. The solar sensor is fitted in the centre of the instrument panel.

Sensor for automatic recirculated air control The AUC sensor is fitted on the micro-filter compartment. The AUC sensor detects the following pollutant emissions:
Hydrocarbons (CH)
Carbon monoxide (CO)
Nitrogen oxides (nitrogen monoxide NO, nitrogen dioxide NO2)
The junction box supplies the AUC sensor with voltage. The junction box electronics evaluate the data of the AUC sensor. This evaluated data is sent via the K-CAN to the IHKA control unit.

Evaporator temperature sensor The evaporator temperature sensor measures the outlet temperature of the air at the evaporator to prevent freezing over. The evaporator temperature sensor is directly connected to the IHKA control unit.
Ventilation temperature sensor The ventilation temperature sensor is integrated in the solar sensor. The ventilation temperature sensor measures the delivery temperature directly at the upper ventilation air vents.
Coolant pressure sensor The coolant pressure sensor is fitted in the pressure line between the condenser and the evaporator. Depending on the sensor signal, the air-conditioning compressor is regulated by the IHKA control unit in the event of excessive refrigerant pressure. The junction box supplies the coolant pressure sensor with voltage. The data is evaluated in the junction box electronics. The prepared data is sent across the body CAN (K-CAN) to the IHKA control unit.
Microfilter
A microfilter with activated carbon is built into the IHKA. The activated carbon filter makes an additional contribution to cleaning the fresh air that enters of gaseous pollutant emissions. There is no detection of the state of the filter.

Notes for Service department
Observe the following information for service:

General information
The following general data is provided for servicing the IHKA:

Running in the air-conditioning compressor

IMPORTANT: After replacement, allow the air-conditioning compressor to run in.

After replacement of the air-conditioning compressor or refilling the refrigerant circuit, the air-conditioning compressor must be run in. Running in is required to ensure lubrication (oil distribution). Running in can only be carried out using the BMW diagnosis system.
For this running in, the air-conditioning compressor must be operated within the specified engine speed range. Here, the oil volume filled by the manufacturer mixes evenly with the liquid refrigerant.

IMPORTANT: Do not exceed the specified engine speed.

If the engine speed exceeds the specified engine speed range, running in is aborted automatically. The running-in procedure must then be repeated in its entirety.

Replacement of the electrical auxiliary heater
The electrical auxiliary heater can be replaced in service (the heater/air conditioner must be completely removed).

Coding and programming
Coding
When coding the vehicle-specific data, the following details (among others) are taken into account:
Engine variant (diesel engine or petrol engine)
Version of the control unit (IHKA)
Programming
Flash programming of the IHKA control unit via the K-CAN is possible.

Personal Profile
Almost all functions of the Personal Profile are set in the vehicle itself (see Owner's Handbook at "Personal Profile": personal settings for a maximum of 3 remote controls via the display in the instrument cluster or the Central Information Display).

Country-specific versions
The temperature display can be switched to °C or °F using the on-board computer function.
No liability can be accepted for printing or other errors. Subject to changes of a technical nature

 

some info on the Integrated Heating/air Conditioning Control (IHKS)

Integrated Heating/air Conditioning Control (IHKS)

Integrated heating-air conditioner control, IHKS
This functional description covers the integrated heating / air conditioner control. The IHKS can be used to adapt the in-car climate to the individual needs of the passengers. Information is exchanged between the vehicle components involved via the body CAN data bus.
There are no differences for left-hand drive and right-hand drive vehicles. The control unit with operating unit is always fitted in the same position in the vehicle.
The control unit has the following functions (see also individual functional descriptions):
Temperature control
Air distribution
Air flow control
Recirculated-air mode
Heated windscreen and rear window
Brief description of components

Control unit with operating unit
The IHKS control unit records the signals of the IHKS components and controls/regulates the heating and air conditioning process. The control unit is at the same time the operating unit of the IHKS.

The IHKS control unit also contains the bank of switches. The bank of switches can be used to operate the seat heating (if installed), the heated windscreen and heated rear window, as well as the electrical power windows. The center lock button as well as the switches for the fog lamps and rear fog lamp are also built in.

Heater/air conditioner
The IHKS heater / air conditioner is fitted underneath the instrument cluster in the centre, at the front bulkhead.
The heater/air conditioner performs the tasks:
Generation and regulation of air quantity
Air distribution, air mixture (stratification) and air dehumidification
Transfer of refrigerating output generated by the cooling circuit
Transfer of heat output delivered by the refrigerant circuit
The heater/air conditioner is composed of the following components:
Evaporator The evaporator plates are cooled by the coolant evaporating inside. The air-mass flow supplied by the blower is guided over the cool evaporator plates. The air is cooled and dried and guided into the vehicle interior.
Heat exchanger for heating system On the IHKS, no heating system heat exchanger sensor is fitted.
Flaps with drive and mechanical system The flap motors are connected directly to the IHKS control unit. Three flap motors are fitted in the IHKS. The flaps serve to distribute the air and to mix hot and cold air.
Fresh air recirculated-air flap: the amount of clean air drawn in by the blower is regulated with this flap.
Air distribution flap: The air distribution flap mechanical system mechanically adjusts the air distribution flaps. The air distribution flap mechanical system is driven by the air distribution flap motor. The air distribution flap motor has the task of setting the air distribution by means of a cam disk. The air distribution flap motor has no detection of the actual position. In order to ensure unique positioning of the cam disk nonetheless, there are 2 cams of different widths on the cam disk. The micro-switch signals to the IHKS control unit that the cams have been passed over. This mechanism achieves reliable and rapid positioning of the cam disk.
Temperature mixing flap: The air-mass flow is guided through the evaporator. The air-mass flow is cooled and dried in the evaporator (when the air conditioning system is switched on). Subsequently, the temperature mixing flap guides the air-mass flow (depending on the set desired temperature value in the IHKS controls) fully or partially over the heat exchanger for the heating system and the electrical auxiliary heater (diesel engine).

Blower with blower ballast resistor The blower creates the necessary air-mass flow. The blower is fitted after the fresh air recirculated-air flap in the heater/air conditioning system (pressing blower arrangement). The blower ballast resistor enables a manual 4-stage fan setting on the IHKS controls.
Electrical auxiliary heater The electrical auxiliary heater based on the PTC principle is fitted in the heater/air conditioner. The electrical auxiliary heater directly heats up the air to adjust the temperature of the vehicle interior. The electrical auxiliary heater is only fitted in diesel engines.
Radiator fan
The radiator fan and the engine cooling are also required for cooling the condenser. The radiator fan is activated by the Digital Engine Electronics.
Signal path:
IHKS control unit -> K-CAN -> Junction box electronics -> PT-CAN -> DME -> Radiator fan

A/C compressor
The air-conditioning compressor compresses the refrigerant taken in by the evaporator. The refrigerant is pressed towards the condenser. The air-conditioning compressor is switched by the compressor coupling. Activation is initiated by the IHKS control unit.

Condenser with integrated drier flask
In the condenser, gaseous refrigerant is converted into liquid refrigerant. In the integrated downstream drier flask, any water present in the refrigerant circuit is bound. The drier insert can be replaced.

Sensors
Evaporator temperature sensor The evaporator temperature sensor measures the outlet temperature of the air at the evaporator to prevent freezing over. The evaporator temperature sensor is directly connected to the IHKS control unit.
Coolant pressure sensor The coolant pressure sensor is fitted in the pressure line between the condenser and the evaporator. Depending on the sensor signal, the air-conditioning compressor is regulated by the IHKS control unit in the event of excessive refrigerant pressure. The junction box supplies the coolant pressure sensor with voltage. The data is evaluated in the junction box electronics. The prepared data is sent across the body CAN (K-CAN) to the IHKS control unit.
Microfilter
A microfilter with activated carbon is built into the IHKS. The activated carbon filter makes an additional contribution to cleaning the fresh air that enters of gaseous pollutant emissions. The state of the microfilter is not picked up.

Notes for Service department
Observe the following information for service:

General information
The following general data is provided for servicing the IHKS:

Running in the air-conditioning compressor

IMPORTANT: After replacement, allow the air-conditioning compressor to run in.

After replacement of the air-conditioning compressor or refilling the refrigerant circuit, the air-conditioning compressor must be run in. Running in is required to ensure lubrication (oil distribution). Running in can only be carried out using the BMW diagnosis system.
For this running in, the air-conditioning compressor must be operated within the specified engine speed range. Here, the oil volume filled by the manufacturer mixes evenly with the liquid refrigerant.

IMPORTANT: Do not exceed the specified engine speed.

If the engine speed exceeds the specified engine speed range, running in is aborted automatically. The running-in procedure must then be repeated in its entirety.

Replacement of the electrical auxiliary heater
The electrical auxiliary heater can be replaced in service (the heater/air conditioner must be completely removed).

Coding and programming
Coding
When coding the vehicle-specific data, the following details (among others) are taken into account:
Engine variant (diesel engine or petrol engine)
Version of the control unit (IHKS)
Programming
Flash programming of IHKS control unit via the K-CAN is possible.
No liability can be accepted for printing or other errors. Subject to changes of a technical nature

 

and last but not least: Integrated Heater Control IHS

Integrated heater control IHS
This functional description covers the integrated heating control, IHS. The IHS can be used to adapt the in-car climate to the individual needs of the passengers. Information is exchanged between the vehicle components involved via the body CAN data bus.
There are no differences for left-hand drive and right-hand drive vehicles. The control unit with operating unit is always fitted in the same position in the vehicle.
The control unit has the following functions (see also individual functional descriptions):
Temperature control
Air distribution
Air flow control
Recirculated-air mode
Heated windscreen and rear window
Brief description of components

Control unit/operating unit
The IHS control unit records the signals of the IHS components and controls/regulates the heating process. The control unit is at the same time the operating unit of the IHS.

The IHS control unit also contains the bank of switches. The bank of switches can be used to operate the seat heating (if installed), the heated windscreen and heated rear window, as well as the electrical power windows. The center lock button as well as the switches for the fog lamps and rear fog lamp are also built in.

Heater/air conditioner
The IHS heater/air conditioner is fitted underneath the instrument cluster in the centre, at the front bulkhead. heater/air conditioner performs the tasks:
Generation and regulation of air quantity
Air distribution, air mixture (stratification)
Transfer of heat output delivered by the cooling circuit
The heater/air conditioner is composed of the following components:
Heat exchanger for heating system On the IHS, no heating system heat exchanger sensor is fitted.
Flaps with drive and mechanical system The flap motors are connected directly to the IHS control unit. Three flap motors are fitted in the IHS. The flaps serve to distribute the air and to mix hot and cold air.
Fresh air recirculated-air flap: the amount of clean air drawn in by the blower is regulated with this flap.
Air distribution flap: The air distribution flap mechanical system mechanically adjusts the air distribution flaps. The air distribution flap mechanical system is driven by the air distribution flap motor. The air distribution flap motor uses a Cam disk to set the air distribution. The air distribution flap motor has no detection of the actual position. In order to ensure unique positioning of the cam disk nonetheless, there are 2 cams of different widths on the cam disk. The micro-switch signals to the IHS control unit that the cams have been passed over. This mechanism achieves reliable and rapid positioning of the cam disk.
Temperature mixing flap: Subsequently, the temperature mixing flap guides the air-mass flow (depending on the set desired temperature value in the IHS controls fully or partially over the heat exchanger for the heating system and the electrical auxiliary heater (diesel engine).

Blower with blower ballast resistor The blower creates the necessary air-mass flow. The blower is fitted after the fresh air recirculated-air flap in the heater/air conditioning system (pressing blower arrangement). The blower ballast resistor enables a manual 4-stage fan setting on the IHS controls.
Electrical auxiliary heater The electrical auxiliary heater based on the PTC principle is fitted in the heater/air conditioner. The electrical auxiliary heater directly heats up the air to adjust the temperature of the vehicle interior. The electrical auxiliary heater is only fitted in diesel engines.
Microfilter
A microfilter with activated carbon is built into the IHS. The activated carbon filter makes an additional contribution to cleaning the fresh air that enters of gaseous pollutant emissions. The state of the microfilter is not picked up.

Notes for Service department
Observe the following information for service:

General information
The following general data is provided for servicing the IHS:

Replacement of the electrical auxiliary heater
The electrical auxiliary heater can be replaced in service (the heater/air conditioner must be completely removed).

Coding and programming
Coding
When coding the vehicle-specific data, the following details (among others) are taken into account:
Engine variant (diesel engine or petrol engine)
Version of the control unit (IHS)
Programming
Flash programming of IHS control unit via the K-CAN is possible.
No liability can be accepted for printing or other errors. Subject to changes of a technical nature

 

OK to update this. So it turns out to be the controller, but the funny thing is that it working normal now. but at least i know what needs to be replace eventually.

Thank you for all the help. I have the Servo motor just in case.