Mercedes w203 heating problem

[Sohail123]

Hi guys im new member n its my first post. i need some help here

I have mercedes c class 2006 c220 cdi sport. Problem is interior heater doesnt produce hot air. Thermostat seems to be fine cuz engine temp goes upto 90 but still cold air inside. One of my friend told me it could be a matrix problem but thats a very big job to do. Nothing came up on star computer aswell.

 

[Frosty149]

Check the connections and fuses before dismantling, there is a reset procedure and some 'known' issues described at length on the forums - search on here and google. Not heard of matrix probs, fortunately, valves, electrical and mechanical etc though.
Be systematic and rule out the easy stuff first, otherwise you'll be digging deep into the dash aimlessly.
Someone with more specific experience will doubtless be able to help more...

 

[Sohail123]

Thanks for ur kind reply frosty but i did the reset thing but no luck. Thats what am looking for what easy and inexpensive things i could try more to solve this issue before opening the whole dashboard and matrix which is very very expensive and long procedure

 

[LostKiwi]

I'm assuming you have climate control with dual heat zones? If so do both sides have the same problem?

 

[Sohail123]

Thanks for ur kind reply lostkiwi yeah both sides have same issue.

 

[LostKiwi]

Ok so the issue must be with a component common to both sides (of which there are very few).
Do you get any heat or is is stone cold? Also did this happen suddenly or gradually?

 

[Sohail123]

There is heat but very very minimum. When i bought this car the issue was there so dont know the history.

 

[LostKiwi]

Ok fond where the heater pipes go through and disconnect them then with a garden hose try flushing one way then the other.

 

[Sohail123]

I found one pipe near the engine in the middle but couldnt fine other one can u send me any pic of pipes?
Also i noticed one thing today thay engine temperature goes to 80 max after like 5 miles drive but on motorway keep decreasing to 60 sometimes 50 and in town or busy roads goes again to 80. Do u think drop in engine temperature is normol? If not then is it the thermostat?

 

[rf065]

The engine temp should go to approx 85 - 90 and stay there all day, change the thermostat first & then see if the heater works.

Russ

 

[Frosty149]

No heater function and erratic engine temperature whilst running?
Maybe airlocked, and/or coolant shortage?
A flush out and refill costs nothing and rules it out if not a cure...

 

[LostKiwi]

As above change the thermostat. Personally I'd only use genuine.

 

[Sohail123]

I spoke with one of the local mercedes mechanics and they booked me in for 10 october. Meanwhile guys please can u help me whats the exact method of flushing pipes and where they r located?if someone can post any poctures or diagram please

 

[Sohail123]

Also do i need to replace thermostat housing or just thermostat which goes inside?

 

[Frosty149]

Just the inside unit...

 

[Sohail123]

Hi guys am back again. I changed the thermostat now engine temp stays on 90 but still only 10% heat could come back so problem is not solved. What should i do now

 

[LostKiwi]

As before, flush the matrix using a garden hose. Flush repeatedly in both directions.

 

[Frosty149]

As before, flush the matrix using a garden hose. Flush repeatedly in both directions.

Agreed ^^
For the sake of simplicity, is it not possible to flush the matrix in Situ via the engine bay hose connections?
There are proprietary flushing agents that can be added to the system, but Lost Kiwi's approach will rule out or confirm a blockage immediately.
Next steps will likely be more intrusive and a maybe a few £'s.

 

[LostKiwi]

Agreed ^^
For the sake of simplicity, is it not possible to flush the matrix in Situ via the engine bay hose connections?
There are proprietary flushing agents that can be added to the system, but Lost Kiwi's approach will rule out or confirm a blockage immediately.
Next steps will likely be more intrusive and a maybe a few £'s.

Yes - just trace the heater lines where they go through the bulkhead and disconnect at the easiest place to get to.

 

[Sohail123]

I found one pipe which is almost in the center near engine and there was no water in it which means there is a blockage but couldnt find the other one even my local mechanic couldnt find it. Mercedes garage asking for £100 only to check and find the issue. Can u guys upload any picture or diagram of where both pipes r located so i can disconnect them and flush them otherwise i have to pay alot of money to solve this issue.

Kind regards