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Old Mar 21, 2023 | 09:01 PM
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Now that I have the blend doors done and are working correctly, I was wondering if I could get opinions on replacing the control unit in the car. It doesn't blow air according to the meter that shows the stack growing as the fan speeds up. Doesn't seem like that big of a job. Will it work better? Are they ALL **** from the factory? Thoughts and opinions?
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Old Mar 21, 2023 | 09:24 PM
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Your saying your air out put is less than expected? Does the fan speed change at all?
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Old Mar 21, 2023 | 09:51 PM
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Does air come out of the vents you select? No air coming out of the defroster vents when the dash vents are selected? If the air path isn’t working, you’ll be able to hear the fan speed increase but won’t be able to tell as the air goes up to the defroster or down to the floor.
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Old Mar 22, 2023 | 08:06 AM
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I should have been more clear. The unit works. If I want a higher fan speed but not full blast I can't access it. It's more or less all the way on or not a peep. Anywhere between full and minimal is non existent. When you get to the top of the fan gauge, it wakes up and goes hurricane. The air comes out of the vents I select, yes.

However, I drove it today and the heat was on auto set at 73. All of a sudden the heat came on and it was blowing at a nice clip as if it had selected it. Not full blast but I could hear it blowing. I've owned the car for a couple years and it never did that before so it must have been an issue when I bought it. That tells me the control unit is junk, no? It can select the fan speed so we know that's ok but the unit won't allow me to do it.

I thought if I changed out the head unit for a newer or refurbished model it would work better than the one I currently have. I just did the actuators and I tell ya, it was quite a relief after all that work to have the heat working properly. I was dreading the fact it wouldn't. Why not go all the way and have the head unit work right?

What a great first world problem to have.
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Old Mar 22, 2023 | 09:42 AM
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There are several repair businesses, you can send them your hvac control module, the internet is your friend.
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Old Mar 22, 2023 | 10:40 AM
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One place you could try is Travis@Vettetronics. Phone# is (618) 975-3607. Good luck
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Old Mar 22, 2023 | 02:21 PM
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Originally Posted by Phil R
I would try and get a proper diagnosis. It could be a vacuum leak, could be a bad blower motor, could be a ground issue, etc.
I'm thinking the blower motor and it's components are fine being proved through the automatic feature that comes on by itself and is at half fan speed. The unit CAN go there. I just can't make it happen through my head unit.

Don't take this the wrong way but have you been to a mechanic lately? Hold onto something if you have to go because you're about to get floored. Anything is doubled as of 6 mths ago. Rotors? Up 300%. From 30 to over 90 bucks! Pads are now 80 bucks for metallic.

So I guess what I'm saying is no mechanic will be looking at my car on my dime. Prices are flat to falling slightly on these cars in general though. Saw a low mileage 04 Z06 yesterday for 41k! LOL!
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Old Mar 22, 2023 | 03:21 PM
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Originally Posted by The Former
I should have been more clear. The unit works. If I want a higher fan speed but not full blast I can't access it. It's more or less all the way on or not a peep. Anywhere between full and minimal is non existent. When you get to the top of the fan gauge, it wakes up and goes hurricane. The air comes out of the vents I select, yes.

However, I drove it today and the heat was on auto set at 73. All of a sudden the heat came on and it was blowing at a nice clip as if it had selected it. Not full blast but I could hear it blowing. I've owned the car for a couple years and it never did that before so it must have been an issue when I bought it. That tells me the control unit is junk, no? It can select the fan speed so we know that's ok but the unit won't allow me to do it.
.
Check the blower motor resistor and it's connection.
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Old Mar 22, 2023 | 03:33 PM
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Originally Posted by Smoken1
Check the blower motor resistor and it's connection.
I'll give that a whirl. Thank you for the advice.
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