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ac fan speed. I checked all my outlets with a pyrometer while driving today and all were blowing around 46 degree air so I know the ac is working and the blend doors are good but when set to max, you would be hard pressed to blow out the flame on a bic lighter. The car does get cold but that fan speed seems awfully low. Any ideas?
Thanks C5diag
I made it to step 2. Each setting of fan speed works, just not enough cfm's. Step 2 is "go to testing for intermittent and poor connections in diagram......Question is which diagram.
Diagram below…the “control” wire is the tan wire on the blower motor control module…it goes to the HVAC module pin C11 (Blower Speed)…helps to have a Tech 2 or any bidirectional scan tool to perform the diagnosis…a 12 volt incandescent test light helps too.
Solid info. I think before I start digging into it too deep I will try that calibration of the blend doors just to rule it out. As always......start with the simplest possibility.....Akums Razor
Solid info. I think before I start digging into it too deep I will try that calibration of the blend doors just to rule it out. As always......start with the simplest possibility.....Akums Razor
The blend or air temperature actuators control the temp so if your temp is responding a calibration won’t help…if you don’t hear the fan blower speed increase it may be a bad module possibly.
Here are the readings after the re calibrate. I should have taken pre calibrate measurements but my meter hadn't arrived yet.....1st is center vent.....2nd is door vent. Maybe it's just me but I drive my Impala all week and it blows well.
Here are the readings after the re calibrate. I should have taken pre calibrate measurements but my meter hadn't arrived yet.....1st is center vent.....2nd is door vent. Maybe it's just me but I drive my Impala all week and it blows well.
If I'm seeing this correctly, your center vent is 11° warmer than the door vent. You may indeed have blower issues, but an 11° variance is pretty substantial in my opinion......
If I'm seeing this correctly, your center vent is 11° warmer than the door vent.
Looking at the meter on Amazon, the top left group of numbers is temperature, top right group is humidity, and the big numbers are wind speed — though no clue what units. Whatever the units are, the numbers seem to indicate a difference of over 100!
OK, tomorrow the windows get ceramic tint. I'll see how much that helps keep the car cool. On a long drive it's not that much of an issue because the car eventually cools down and is comfortable.
Planning on bringing it to the dealer if that doesn't help but I did notice one thing tonight while testing the airflow again. Regardless of the mode, center, floor, floor/def or just def, there is always air blowing thru the vents. Checked the DIC and used my scan tool and no codes at all in any segment. I guess the question is can the blend door actuators fail but not give a code?????????????
Air distribution is controlled by vacuum so if you have a vacuum leak anywhere from the vacuum line behind the intake manifold to the vacuum reservoir aft of the PCM and then to the HVAC system in the dash you won’t be able to get the air to where you want it…if you take it to a dealership and I don’t know why you would want to take it there expect EVERYTHING in the HVAC system to be changed…don’t be surprised by a 2-3K bill !!
I bet you that's whats going on which is why there's no errors.. Not the actuators themselves its the vaccum. Now that's something my guy can check with a smoke machine.....Is that vacuum tank below the battery?
Last edited by yellow2007; Aug 7, 2023 at 07:45 PM.
fan speed
