Official A/C Deletion - Big Picture uploaded

toayoztan

Moderator
I was busy working on buddy's vette. I separated everything "A/C" from the all the harnesses, now just looking to clean it up. Separating
the entire harness as I did is NOT necessary, as there is not much to remove. However, I opted to do so in order to ensure that if anything
needed to be corrected to this deletion mod, I can easily find the entire harness, modify it as necessary, and retrace everything.

This will be the official thread where you guys can refer to on what you need to remove. I will clean up this post to make it a more proper
How-To once we get it all checked over and finalized. I'll also add more pics on where some of the components are later.

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Here is a picture of the diagram. I need someone to confirm what they can. The bolded section below is what I really need help with.
The gray shaded is what I THINK we can remove, and still have functioning HVAC system for non-a/c air and heater.

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THESE PARTS ARE RELATED TO THE FUNCTION OF THE A/C UNIT

A/C Amplifier (A17) - located on bottom left of diagram. This appears to actually control the A/C system when you push that magical A/C button.
This is connected directly to the button, if you follow it to the controls. It also goes to the engine bay parts, such as relays and compressor.
Therefore, this does not seem necessary to keep.

A/C Dual Pressure Switch - I believe this switch basically prevents the A/C from working if there is insufficient pressure in the refrigerant system.
Therfore, this is also not needed, and as you see is attached to the A/C amplifier.

A/C Thermistor - As the name implies, it's related to temperature of the current. This is basically an overcurrent protector for the A/C amplifier.
Again, not needed if removing the A/C amplifier.

A/C Condenser Fan Relay No 2 and No 3, Condenser Fan Motor, CDS Fan 30A fuse - As the name again implies, this is related to the condenser
and its fan operation. You can remove this.

A/C Magnetic Clutch Relay, A/C Magnetic Clutch and Compressor Sensor - These are related to the actualy compressor operation. If you've
removed the compressor, you obviously have no use for these.

10A A/C - This fuse is for the A/C Amplifier. You can remove this too.

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THESE PARTS ARE RELATED TO THE AUTO FUNCTION (REGARDLESS OF WORKING/INTACT OR REMOVED A/C SYSTEM)

A/C Solar Sensor, A/C Room Temp Sensor, a/C Ambient Temp Sensor - I am not 100% on these. If my memory serves me right, when it is
set to the AUTO function, the unit basically determines if to use the Heater or AC, and determines how high or low the fan setting is. What I
am not sure about is if I set it to the AUTO setting with the temp to cool, then does the AC automatically kick on when it needs to, or do you
still have to push the AC button? I do not remember, as it has been a while since I've had A/C. I imagine the Auto function can still be useful
in cooler weather and winter, but useless in the summer without A/C. However, I am not too hung up on keeping the Auto function. So to make
things less complicated, I am contemplating on removing these anyway. However, if I remove these things, I am also concerned if the temperature
and fan settings will still work perfectly fine MANUALLY adjusted.


A/C water temp sensor - Located on the left portion of the Auto A/C Amplifier with a yellow and black wire going to it. I assume we need to
keep this. This is located in the heater core area, and is for the Auto A/C.

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I know, long post, but any help and collaboration will be great.

These two pics are exactly the same, the first one is just smaller to make it easier for those with smaller monitors to view. Of course, you can always
right click and save to your computer too.

acwiringdiagramomit.jpg


acwiringdiagramomit.jpg


Bryan
 

ALLensTRAC

New member
I see a few problems with removing the ac amp(HVAC ECU BTW). First the heater relay is grounded through the ecu on the switched side so that will need to be grounded with a switchable source. Also it looks as though the air mix servo is completely controlled by the ac amp. If you have no control of this you will not be able to switch between full heat or just ambient air. I planned to remove all this wiring too but I am keeping the amp until I can figure out air/mix control. Maybe the use of a non-AUTO system from a 182 :shrug: ? IDK yet but i will look into it more once my interior goes back in.
 

toayoztan

Moderator
Are you referring to the A/C amplifier or the Auto A/C amplifier?

The A/C amplifier is for the A/C (compressor, etc.). The Auto A/C amplifier is for everything else, which I assume you are referring to the HVAC ECU.

The Auto A/C amp I am leaving in place, allowing the servo-mix motor and Heater relay to still fully function.

Bryan
 

toayoztan

Moderator
I'm moving this to Club Chat to get more exposure, as a few number of us were interested in this. This will probably end up in the "how to" section in the end.

Bryan
 

toayoztan

Moderator
***I've already edited and fixed the diagram to reflect these changes from below***

Alright, so after studying this a bit more, there's a few errors I caught on my own diagram.

After comparing it to the Non-Auto AC diagram, there's a mistake with deleting the thermistor. I just simply goofed and hadn't realized that the thermistor shown in the diagram above is for 2 circuits. You only need to delete the one that is for the A17 AC Amplifier, not the AC Auto Amplifier, you need to leave this in place.

Also, the three sensors coming off the AC Auto Amplifier that I grayed out to remove needs to be in place for the Auto Function to work. The Auto Function can still be used and useful in cooler months of the seasons without a functioning AC. Therefore, I am leaving all three of these sensors in place.

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AUTO Function

According to a Parts Location diagram in another section of the BGB regarding AC, the AUTO-specific parts are the AUTO A/C amplifier, Room Temp Sensor (located below key ignition area), Water Temp Sensor (the one located in/near the heater core, not the radiator), Power Transistor, and Solar Sensor (on right side of dash near windshield).

I also believe the Ambient Temp Sensor (located in front of engine bay near condenser/radiator), A/C System Amplifier, Air Mix Control Servo Motor are needed despite not being labeled fr AUTO A/C, because I did not see these part in the NON-AUTO wiring diagram.

I mention this in case anyone who wants to ditch their AUTO function. However, it isn't as simple as removing these components, as the Heater Relay and function is also tied in within this amplifier. Therefore, one would need to compare both wiring diagrams and modify the wiring.

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I will edit and post a new diagram to reflect these changes above when I get the chance, but for anyone lurking on this thread and removing their AC, just keep this in mind.

Bryan
 

l0ch0w

New member
The only thing I would say is be careful if you plan on removing that 30A CDS Fuse. I have to check, but its possible it controls more than just condenser fans.
 

toayoztan

Moderator
I'll double check on it. When I removed the wires going to it, it appeared only had the condenser fan wires were attached to the fuse. I didn't look at the box itself nor did I physically remove the fuse yet, just the condenser fan wires. If anything, I suppose I could leave it in place for now, since I need to keep that fuse box anyway.

Bryan
 

l0ch0w

New member
I double checked, theres nothing on it but the fans... I just remember digging into my harness thinking "why is this connected here" and when I looked at the diagrams it didnt show at all on one, but it did on another...
 

toayoztan

Moderator
Cool thanks for checking and the heads up!

I'm still trying to decide what to do about looming up my wires. I don't have time to wait and order stuff from online (getting really behind, and need to get this back together!), but there's a "wire/electrical" place down the street from me that has a bunch of stuff, and it's a company that's dedicated to just wiring and loom. So I will probbly just check them out. If anything, I just need something that will loom up the interior. It really won't need to be anything too special to guard against heat or too much dust. I can think and research something cool and special later down the road for anything in the engine bay, especially when I get to my EMS wiring.

Bryan
 

phattyduck

New member
You will want to leave the CDS Fan fuse and A/C fan in place. When the motor is running hot (water temp), both fans run full speed. The only feature you want to get rid of is the series operation of the fans for 'A/C on but motor not hot' operation. You'll want to wire the second fan to turn on with high water temp just like the Radiator Fan. (the really do the same job in all operation modes, they are just named different for some reason)

The tough part is that the fans are switched on opposite sides (one on the power side, one on the ground side) so you will have to figure that out. The idea here is that if one fan fails, you still have enough cooling to keep your motor from overheating.

-Charlie

Edit: it looks like things might be a bit different than the fan operation I am used to on my Camry... ignore if my above statements are incorrect about the fan operation (serial vs. parallel operation).
 

toayoztan

Moderator
Yea I'll have to follow the diagram a little more closely if someone wants to retain their condenser fan.

I plan on running two slim fans with an aftermarket radiator with relays hooked up into the stock water temp sensor, so I didn't bother with figuring out the issue of retaining the condenser fan. You could also just hook up a relay to the condenser fan with fuse and signal wire from the radiator fan or water temp sensor (basically series or parallel, either would work since it's just a signal wire to the relays), and would have both fans kick on when it gets to temp.

Bryan
 
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