Need HVAC Schematics
This is all I have that has HVAC, I have the A/C diagram too.
Attachment 190481
Attachment 190481
Teching In
Joined: Jul 2007
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That's great Mike.
I was looking through those schematics and it looks like all it does it request the A/C to turn on. I was wondering how the HVAC controls the Fans and the heater. I really hate to bother you with this and great job on the supplied info.
Jersey Mike,
Chime in and tell him what your trying to do.
I was looking through those schematics and it looks like all it does it request the A/C to turn on. I was wondering how the HVAC controls the Fans and the heater. I really hate to bother you with this and great job on the supplied info.
Jersey Mike,
Chime in and tell him what your trying to do.
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Thanks, Rob.
I'm attempting to replace the climate control unit in the 2000 T/A with that of a 2003-2007 CTS. I understand that many of the features of the newer, CTS unit (like driver & passenger climate personalization, heated seats, etc) can't be used, however I'm hoping it can retain the primary features.
I'm attempting to replace the climate control unit in the 2000 T/A with that of a 2003-2007 CTS. I understand that many of the features of the newer, CTS unit (like driver & passenger climate personalization, heated seats, etc) can't be used, however I'm hoping it can retain the primary features.
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Verdad Gallardo Teching In
Joined: Jul 2007
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JM,
If you want to do this with the CTS HVAC it will be a major project to control the heat. There must be a control for the fan though.
Teching In
Joined: Jul 2007
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Shoemike,
Do you have any schematics for the Fan control?
Jersey Mike,
Can you get me a picture of the original HVAC control? Details on how you control heat, cold, and the fan?
BTW, Thanks SM for helping us on this one.
Do you have any schematics for the Fan control?
Jersey Mike,
Can you get me a picture of the original HVAC control? Details on how you control heat, cold, and the fan?
BTW, Thanks SM for helping us on this one.
Teching In
Joined: Jul 2007
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Yes that would be the blower motort. I looked in that post and the third picture over from the left has a connection to the relay but it's coming from the fuse block so I would assume that would power to at and not control it.
I am thinking the info I need for the blower motor is sitting somewhere on another schematic.
I am thinking the info I need for the blower motor is sitting somewhere on another schematic.
The hot/cold dial controls a cable (like on a bicycle brake) that actuates a flapper that bypasses the heater core. The function dial is a vacuum switch combined with an electrical switch. The vacuum side controls valves, which direct air flow through the various vents and the electrical side sends signals to turn on the A/C and blower motor.
I would think that unless the CTS has the same layout, then a retrofit would require taking all of the other controls off of the CTS ducts and somehow fitting them to your car. (Not just the control panel.)
I would think that unless the CTS has the same layout, then a retrofit would require taking all of the other controls off of the CTS ducts and somehow fitting them to your car. (Not just the control panel.)
Here's that picture of the original HVAC controls on the T/A:
The Fan speed is controlled a electrical connector that goes from a relay to the blower motor IIRC, pretty easy to replicate. The temp control is gonna be the hard part, in the ac box theres a flap that will separate or mix the current from the evaporator core or heater core depending on the tension on the cable. The cable is essentially just like a brake cable on a bicycle. The vent position **** is controlled through vacuum lines, and one electrical connection that just turns on the compressor and turns on the blower. PM me if you need help, I actually looked into doing this with a corvette hvac control unit.
Can you tell me how to use this to force the compressor on while the ****/vent is on floor only? It's just not designed to do that on the 97-02 TA and I don't know why.
Specifically if you could tell me which contacts open/close/have voltage/are grounded that would be extremely helpful.
Joined: Nov 2003
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From: Jacksonville, FL (originally from Toronto Canada)
The factory configuration allows the A/C compressor to run in all positions except off. There is nothing you can do with the control switches or wiring that would change that because it's already enabled whenever it's on.
You can manually control the compressor clutch engagement by grounding the dark green with white wire at the A/C Compressor relay in Junction box #2 under the hood on the left inner fender. That grounding is normally controlled by the PCM but you could ground it through your own switch. Just be careful because doing so effectively bypasses all the system checks such as refrigerant pressure so you could damage your A/C system.
You can manually control the compressor clutch engagement by grounding the dark green with white wire at the A/C Compressor relay in Junction box #2 under the hood on the left inner fender. That grounding is normally controlled by the PCM but you could ground it through your own switch. Just be careful because doing so effectively bypasses all the system checks such as refrigerant pressure so you could damage your A/C system.
The newer cars have their ducts and vents designed with CAD and use fluid dynamics to make sure that the air flows precisely around the complex interiors of the car. Society didn't have that (unless you were modeling nuclear warheads or space capsules) in the late '80's/early '90's when the ducts on these cars were being designed.
Our lower ducts don't work so well for cool air and rely on hot air rising. Since they aren't directed ducts, the cold air is just going to hang around at your toes and won't get up to your torso. (That's why Bi-Level is your only option and this configuration is common on cars of the period.)
Yes. I'd like to emulate my 1999 Subaru legacy with the space capsule technology.
That's fine with me. I like to take the tops off in moderate weather and get cooler air at my feet. There's enough air circulation otherwise.
Our lower ducts don't work so well for cool air and rely on hot air rising. Since they aren't directed ducts, the cold air is just going to hang around at your toes and won't get up to your torso. (That's why Bi-Level is your only option and this configuration is common on cars of the period.)