Heater problem

Tiny
VIVEKHB
  • MEMBER
  • 2003 MERCEDES BENZ C230
  • 1.8L
  • 4 CYL
  • 2WD
  • AUTOMATIC
  • 230,000 MILES
My driver side heater does not blow air at all, neither cold nor hot, while my passenger blows hot air. The A/C blows cold air both on the driver as well as passenger side.I synchronized the stepper motors to confirm if all the actuators are working. At present I have removed the dash but still I can"t find the fault. Please if you can suggest what I have to look for. Thanks a lot in advance.
Sunday, May 26th, 2019 AT 8:17 PM

5 Replies

Tiny
KEN L
  • MASTER CERTIFIED MECHANIC
  • 54,144 POSTS
There are 14 actuators for this car can you confirm they are all working? If so I would replace the control module. Can you confirm you have power at the four fuses that run the system? Here are the wiring diagrams so you can see which fuses you should check and letting you know how the system works. Check the connection using this guide if everything is okay replace the module

https://www.2carpros.com/articles/how-to-check-wiring

Check out the diagrams (below). Please let us know what you find. We are interested to see what it is.
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Wednesday, May 29th, 2019 AT 5:39 PM
Tiny
VIVEKHB
  • MEMBER
  • 91 POSTS
Mr. Ken, thanks your reply. Please if you can direct me the relays that I should check. For the diagrams you sent me are too deep for my understanding. But definitely I will change the control module and the blower motor resistor as directed.
Once I replace these I will be in touch with you. Thanks once again. Have a blessed weekend, bye.
Vivek
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Wednesday, May 29th, 2019 AT 7:32 PM
Tiny
KEN L
  • MASTER CERTIFIED MECHANIC
  • 54,144 POSTS
There are no relays just actuators and control modules. Take another look at the wiring diagrams and follow the wires to see how the system works. Please let me know.
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Thursday, May 30th, 2019 AT 11:50 AM
Tiny
VIVEKHB
  • MEMBER
  • 91 POSTS
Sir, my Mercedes C230 Kompressor does not crank after the sunroof glass broke.I checked the starter relay, the fuel pump relay and the fuses. But I don't hear the fuel pump after I give the starter. Please Sir your advice will be highly appreciated.
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Tuesday, July 9th, 2019 AT 7:06 PM
Tiny
KEN L
  • MASTER CERTIFIED MECHANIC
  • 54,144 POSTS
You will need to start a new question for this problem what ever happened on the vent flow issue?
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Wednesday, July 10th, 2019 AT 10:17 AM

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