As I finish up installing the final bits and pieces of the a/c in my car. I'm nearing the end of the project in which I was most worried about because I haven't really heard anything about it. I was wondering, what sort of wiring is going to be needed to be done. The guy I'm working with seems to have an idea in this situation, but I'm clued out.
If anyone knows what kind of wiring is going to be involved in hooking my A/C back up in my S14 SR20 - please let me know It's going to be 30+ degree celcius all week, and with black leather, that's not fun!
Urgent: A/C wiring question..
Re: (ArcherV20)
I would think it would be as simple as using your KA Compressor and using 2 of 4 bolts to mount it. Then try plugging the SR plugs into it. If they DONT. then swap plugs from the KA Harness to the SR harness and plug the A/C in. Im sure its pretty simple.
I got rid of the A/C on my S14 motor.
I got rid of the A/C on my S14 motor.
Re: (ArcherV20)
there should be a plug on the compressor I do believe. Now S13 and S14 wiring is different so I cant help you.
Well, there is a little more that you have to do to get the wiring complete for the A/C to function.
Remove your passenger side kickpanel and ECU and pull it to the side. You will now see the main M63 plug. Unplug it and swing it to the side. Now, there are two 10mm bolts holding that male version of the M63 plug onto the body. Unbolt them and pull that plug out towards you so you can see the back side of it, the wire colors. Now, you will need to find the Yellow/Black wire and the Black/Purple wires. Now, cut both wires about 1 inch or so away from the plug. Now, connect both of those wires together that do NOT go into the plug, in other words, connect the Yellow/Black and Black/Purple wire together that go back into the harness, not the plug.
Now, make sure that your compressor is plugged in. There should be a single wire plug around your compressor. Plug it in. Make sure your A/C fuse and relay are both good.
Change your A/C drier since it probably has exceeded its maximum water/crap absorption levels and will create a restriction in the A/C system. Evac/vacuum/recharge your A/C lines to 1.43lbs of R-134a refrigerant.
Now, your A/C will work with the push of the A/C button on your A/C control unit.
Remove your passenger side kickpanel and ECU and pull it to the side. You will now see the main M63 plug. Unplug it and swing it to the side. Now, there are two 10mm bolts holding that male version of the M63 plug onto the body. Unbolt them and pull that plug out towards you so you can see the back side of it, the wire colors. Now, you will need to find the Yellow/Black wire and the Black/Purple wires. Now, cut both wires about 1 inch or so away from the plug. Now, connect both of those wires together that do NOT go into the plug, in other words, connect the Yellow/Black and Black/Purple wire together that go back into the harness, not the plug.
Now, make sure that your compressor is plugged in. There should be a single wire plug around your compressor. Plug it in. Make sure your A/C fuse and relay are both good.
Change your A/C drier since it probably has exceeded its maximum water/crap absorption levels and will create a restriction in the A/C system. Evac/vacuum/recharge your A/C lines to 1.43lbs of R-134a refrigerant.
Now, your A/C will work with the push of the A/C button on your A/C control unit.
Re: (Ramius83)
Is this for the S13 or S14 SR? I believe my wiring was already done all I have to do is plug the harness into the compressor.Ramius83 wrote:Well, there is a little more that you have to do to get the wiring complete for the A/C to function.
Remove your passenger side kickpanel and ECU and pull it to the side. You will now see the main M63 plug. Unplug it and swing it to the side. Now, there are two 10mm bolts holding that male version of the M63 plug onto the body. Unbolt them and pull that plug out towards you so you can see the back side of it, the wire colors. Now, you will need to find the Yellow/Black wire and the Black/Purple wires. Now, cut both wires about 1 inch or so away from the plug. Now, connect both of those wires together that do NOT go into the plug, in other words, connect the Yellow/Black and Black/Purple wire together that go back into the harness, not the plug.
Now, make sure that your compressor is plugged in. There should be a single wire plug around your compressor. Plug it in. Make sure your A/C fuse and relay are both good.
Change your A/C drier since it probably has exceeded its maximum water/crap absorption levels and will create a restriction in the A/C system. Evac/vacuum/recharge your A/C lines to 1.43lbs of R-134a refrigerant.
Now, your A/C will work with the push of the A/C button on your A/C control unit.
The write-up I just gave you was for the wiring at the secondary plug next to your ECU plug. The existing A/C plug at your compressor "should" plug in. But if it doesn't, you can always find one at a pull-a-part or something like that. Or you can wire it without a plug, straight-up, or use a set of butt joint connectors.
Good News: The primary harness from the Compressor and body harness plugged right in with a nice little *click*
Bad News: I flip on the A/C just to test out the workings of it (There is no charge in the system!) and it doesn't seem to be working. The idle does not change, the engine does not shudder or shake, nothing appears to be noticably different with the A/C button turned on.
SO... I assume this means I'll need to do the wiring Ramius talked about. I have some questions about it before I start though and these are just for my own curiousity..:
1) Why does the A/C not just work with the original components and wiring as they are? The clip plugs in fine, why the need for wiring changes? Shouldn't it just know, A/C plugged in, let's rock on!
2) Ramius' wiring instructions, I'm curious to know the function of cutting and splicing those wires together. Is this some kind of bypass? What is this telling my cars computer to do differently as opposed to the stock wiring?
Sorry for the noobish questions! But thanks for all the help so far.
Bad News: I flip on the A/C just to test out the workings of it (There is no charge in the system!) and it doesn't seem to be working. The idle does not change, the engine does not shudder or shake, nothing appears to be noticably different with the A/C button turned on.
SO... I assume this means I'll need to do the wiring Ramius talked about. I have some questions about it before I start though and these are just for my own curiousity..:
1) Why does the A/C not just work with the original components and wiring as they are? The clip plugs in fine, why the need for wiring changes? Shouldn't it just know, A/C plugged in, let's rock on!
2) Ramius' wiring instructions, I'm curious to know the function of cutting and splicing those wires together. Is this some kind of bypass? What is this telling my cars computer to do differently as opposed to the stock wiring?
Sorry for the noobish questions! But thanks for all the help so far.
Re: (ArcherV20)
The reason why your A/C does not work is because of the missing components when you took out your KA wiring harness and ECU. With the KA ECU and harness, the ECU works in-line with the HVAC headunit to work the A/C, along with the triple-pressure switch and thermal control amplifier. When you swap in the SR harness and ECU, many of those wires now go missing because the SR20 ECU does less with the HVAC control in the Silvia. So, swapping this into the 240sx leaves us with missing wires/controls that the Silvia has, ie the advanced climate control in the Silvia. So to make it work, you have to do some wire splicing to get it to work.
By doing the wiring that I mentioned, you are completing the circuit to make the A/C work. When you press the A/C switch on your HVAC control, this will send ground though the Yellow/Black wire. Then the switched ground goes to the Black/Purple wire that you spliced together with the Yellow/Black wire. Then this ground travels through the Triple pressure switch and onto the A/C relay, which is what controls the compressor. The power going to the A/C relay is already there because it is contained in the "headlight/fuse box" wiring harness that you left in the car when you did the swap. So, you only need to complete the ground side of the A/C system.
This is that simple, that is all you need to do. Now, the next thing you need to make sure you do is also make sure one of your A/C wires that is grounded out when you press the A/C button is going to your ECU. The reason you need this is because the ECU needs to know when the A/C is turned on so that it can idle up so the engine doesn't turn off when you turn the A/C on. I am actually working on this as we speak. Right now, the car idles down when you turn the A/C on, but it doesn't shut off. However, I want to get this perfect, so I am looking up this right now. I will let you know what wire to run to the ECU when I find out.
By doing the wiring that I mentioned, you are completing the circuit to make the A/C work. When you press the A/C switch on your HVAC control, this will send ground though the Yellow/Black wire. Then the switched ground goes to the Black/Purple wire that you spliced together with the Yellow/Black wire. Then this ground travels through the Triple pressure switch and onto the A/C relay, which is what controls the compressor. The power going to the A/C relay is already there because it is contained in the "headlight/fuse box" wiring harness that you left in the car when you did the swap. So, you only need to complete the ground side of the A/C system.
This is that simple, that is all you need to do. Now, the next thing you need to make sure you do is also make sure one of your A/C wires that is grounded out when you press the A/C button is going to your ECU. The reason you need this is because the ECU needs to know when the A/C is turned on so that it can idle up so the engine doesn't turn off when you turn the A/C on. I am actually working on this as we speak. Right now, the car idles down when you turn the A/C on, but it doesn't shut off. However, I want to get this perfect, so I am looking up this right now. I will let you know what wire to run to the ECU when I find out.
Just thought I'd throw this in randomly. I'm pretty sure that I need to buy a new A/C Receiver drier for my install to be complete. So I called around and Nissan wanted $150 for them! Then I realized my new job was at a car dealership, went to the parts area and had a brand new receiver drier in my hands in less than an hour for $27!! The savings are miraculous.
Re: (ArcherV20)
The reason why your A/C does not work is because of the missing components when you took out your KA wiring harness and ECU. With the KA ECU and harness, the ECU works in-line with the HVAC headunit to work the A/C, along with the triple-pressure switch and thermal control amplifier. When you swap in the SR harness and ECU, many of those wires now go missing because the SR20 ECU does less with the HVAC control in the Silvia. So, swapping this into the 240sx leaves us with missing wires/controls that the Silvia has, ie the advanced climate control in the Silvia. So to make it work, you have to do some wire splicing to get it to work.
By doing the wiring that I mentioned, you are completing the circuit to make the A/C work. When you press the A/C switch on your HVAC control, this will send ground though the Yellow/Black wire. Then the switched ground goes to the Black/Purple wire that you spliced together with the Yellow/Black wire. Then this ground travels through the Triple pressure switch and onto the A/C relay, which is what controls the compressor. The power going to the A/C relay is already there because it is contained in the "headlight/fuse box" wiring harness that you left in the car when you did the swap. So, you only need to complete the ground side of the A/C system.
This is that simple, that is all you need to do. Now, the next thing you need to make sure you do is also make sure one of your A/C wires that is grounded out when you press the A/C button is going to your ECU. The reason you need this is because the ECU needs to know when the A/C is turned on so that it can idle up so the engine doesn't turn off when you turn the A/C on. I am actually working on this as we speak. Right now, the car idles down when you turn the A/C on, but it doesn't shut off. However, I want to get this perfect, so I am looking up this right now. I will let you know what wire to run to the ECU when I find out.
By doing the wiring that I mentioned, you are completing the circuit to make the A/C work. When you press the A/C switch on your HVAC control, this will send ground though the Yellow/Black wire. Then the switched ground goes to the Black/Purple wire that you spliced together with the Yellow/Black wire. Then this ground travels through the Triple pressure switch and onto the A/C relay, which is what controls the compressor. The power going to the A/C relay is already there because it is contained in the "headlight/fuse box" wiring harness that you left in the car when you did the swap. So, you only need to complete the ground side of the A/C system.
This is that simple, that is all you need to do. Now, the next thing you need to make sure you do is also make sure one of your A/C wires that is grounded out when you press the A/C button is going to your ECU. The reason you need this is because the ECU needs to know when the A/C is turned on so that it can idle up so the engine doesn't turn off when you turn the A/C on. I am actually working on this as we speak. Right now, the car idles down when you turn the A/C on, but it doesn't shut off. However, I want to get this perfect, so I am looking up this right now. I will let you know what wire to run to the ECU when I find out.