Lack of Cabin Heat
Thread Starter
Newbie
Joined: Jan 2024
Posts: 3
Likes: 0
From: Brooklyn
2012 R350
Lack of Cabin Heat
Purchased a 2012 R350 early last year and have been thoroughly enjoying it. First time Mercedes owner so the knowledge base on these forums have been very helpful.
Purchase was back in the Spring of 2023 so we didn’t have to use heat until things turned cold by us (NY). Now I notice HVAC is not distributing heat evenly throughout the cabin. In either auto or manual modes heat only comes out of the front floor vents. I understand that getting heat out of the center dash and rear vents is not an option by design but the rear floor vents and windshield defroster only blow cold air regardless of temp setting on climate control.
After researching the forums I tried resetting the climate control using the defroster/recirculate buttons but this did not activate the reset mode. Is this the correct procedure for a 2012 model?
Wondering if diagnosing this requires STAR or if an independent mechanic can use a non-MB code reader. Seeking tips on the best way to resolve this issue.
Many thanks.
Purchase was back in the Spring of 2023 so we didn’t have to use heat until things turned cold by us (NY). Now I notice HVAC is not distributing heat evenly throughout the cabin. In either auto or manual modes heat only comes out of the front floor vents. I understand that getting heat out of the center dash and rear vents is not an option by design but the rear floor vents and windshield defroster only blow cold air regardless of temp setting on climate control.
After researching the forums I tried resetting the climate control using the defroster/recirculate buttons but this did not activate the reset mode. Is this the correct procedure for a 2012 model?
Wondering if diagnosing this requires STAR or if an independent mechanic can use a non-MB code reader. Seeking tips on the best way to resolve this issue.
Many thanks.
Out Of Control!!
Joined: Apr 2019
Posts: 11,921
Likes: 6,769
From: Silicon Valley
W212 MY'14 M276-3.5NA @75kMi
scan tool
Okay, you are going in the right direction... HVAC module needs to be scanned for faults.
You can purchase a "LAUNCH cReader Elite Benz" scanner for about $150 - It will empower you to really work on your car modules.
HVAC Module ("AAC") has many ways to require service: actuators and valves get disfunctional. You need to know what your car is up to in relation to its 40+ modules....
You can purchase a "LAUNCH cReader Elite Benz" scanner for about $150 - It will empower you to really work on your car modules.
HVAC Module ("AAC") has many ways to require service: actuators and valves get disfunctional. You need to know what your car is up to in relation to its 40+ modules....
