HOW-TO: S14 digital climate control installation

[chuonthis]

I finally got around to putting together a how-to for the S14 digital climate control installation. I'm posting it on my website in case this thread ever gets lost. Let me know what you guys think or if there are any problems/questions.

http://www.chuonthis.com/cars/s14-dcc/

[nrg]

very nice, much better writeup than the other guy on FA.

[chuonthis]

Was there a recent one? Or are you talking about Russ's old one (which I've never actually seen since you can't get to any posts on FA before 2005)? Haha, if it's Russ's.

[NemeGuero]

Awesome write up mang.

[s13speeddrft]

very awesome writeup. If i ever come around to that it will def. be a good source of info. Got to fix the small stuff first though.

[jiggs]

what if i dont have the 2 subharness plugs and no wires? i just have the climate control itself. will i still be able to run it?

[chrisman2k]

^^^^^^ Lmao ^^^^^^

[2iv0 sx]

That's a very good write up!

Could you install one on my S13 for me? =D

[projectRDM]

Originally Posted by nrg

very nice, much better writeup than the other guy on FA.

Ya, that guy's writeup sucked.

Actually, I did that quick and with the notion that if people were attempting it, they at least had a basic understanding of the system in the first place and would know what each unit and piece was. I've now realized that's not the case at all.

[chmercer]

lol, hating on ANYONE who even tried helping people by doing any sort of writeup when he didn't have to do shit at all, GOOD CALL DUDE. i'm thankful for everyone whos done a writeup, helped me get mine working. this writeup particularly helped due to the error code screen, THANKS!

-johny5

[street240]

awesome post

[JohnC]

Thanks for a great writeup!!

[MadScientist]

Your a Mother F-ing God in my book now!!

I was going to wait till I had an S14 Front Clip to pull from... but what the hell... now I have something to play with when the car is on down times.

++ rep galore

Peace
Drew

[chuonthis]

Thanks for the rep. I just found a typo but only in the notes column for wires 7 and 8. I mixed up the + and -. No change to the wiring columns though. Also, I added a little to the thermo control amp description.

@jiggs, if you don't have the plugs for the DCC unit, then you're stuck since the USDM plugs don't fit and I'm not sure if someone will sell you the JDM plugs by themselves since they'd end up with a useless unit too. I guess you could figure out a way to connect wires to each of the pins in the back of the unit but that's almost impossible.

[statik]

wow, nice job on the writeup!

[MAGILLA]

great write up. I will have to book mark it for when I get through the mountain of other projects I need to do first.

[chmercer]

if you have a spare dahs harness, the plug for the security box is the 20 wire plug you need just gotta add some wires by depinning the smaller usdm plug on the hvac box.

[Mattlanta]

VERY NICE!

This is really easy to read...thanks for taking the time!!!

[S14TEVE]

WOW. good job. I will be using this write-up when my DCC comes in. JDM TYTE YO! mad props, thanks!

[95Blue240sx]

Holy crap man thats a great write up. The only thing that would make it better would be to have larger pics.

Would you mind if I made a PDF out of that page? Webpages seems to disappear over time.

[addikted2bass]

you the man!

[Mattlanta]

I found this write up so helpful even before I was ready to do mine. Just understanding what was involved helped tremendously.

Now I have a Kouki S14 clip, which I am using for my SR swap, and when purchasing it I made sure to find one with all the DCC parts in tact.

MY ONLY QUESTION:
The write up says you can't use the JDM S14 fan control amp, but then later in the install it looks like that is what is being used and a hole is cut for it. Can someone clarify if I can use the JDM S14 one or if I will have to buy this part form another donor? Can I still use the S14 JDM one, but I have to do a modification that would not otherwise be required?

That's the only part I was not completely clear on. Thanks in advance for anyone's help!

[projectRDM]

You can't use the US blower resistor. The JDM one is fine, or you can use an S13 or Q45 resistor, you just need to flush mount whatever you choose into the evaporator case to clear the glovebox.

[Mattlanta]

Originally Posted by R240NA

You can't use the US blower resistor. The JDM one is fine, or you can use an S13 or Q45 resistor, you just need to flush mount whatever you choose into the evaporator case to clear the glovebox.

Thanks! That's what it looked like in the photos. I guess it was a typo and he meant to say you can use any one except the USDM S14.

[chuonthis]

Weird, I'm not getting notifications of replies on this thread.

Mattlanta, I said the fan control amp (Russ calls it the blower resistor) can be taken from *any* donor. It's the mounting shield that can't be from a JDM S14. I can maybe update the page later to show pictures of the difference. I'm gonna clean out my evaporator unit some time soon anyway (smells like crap when AC is on) so I'll have to take stuff apart anyway.

[Bandwagon240sx]

Just wanted to say thanks for that awesome write up! I just scored the controller, complete subharness and all the sensors on ebay so I am looking forward to getting this working in my car. I cant stand way the factory AC operates. With the complete subharness I shouldn't have to rewire much except repinning the air mix motor correct? It almost seems like that would be too easy.

[chuonthis]

You're right, that does sound too easy. Now that I think about it, what I wrote in my write up about having the complete subharness isn't right at all, unless you had the complete Main harness. This is what Russ told me a long time ago:

"It's basically easier, if you have a clip, to cut the harness out separately, you'll have a subharness with just a few leads to connect, power, ill, ground, and the blower motor."

Makes sense to me since you probably don't want to replace the entire Main harness. So really, what you should probably do is keep the wires/plugs that run to each of the 3 sensors, the ones that run to each of the 4 door motors (intake, mode, bi-level, air mix), and the ones that run to each of the control amps (thermo and fan). Then find sources for illumination, power, and ground. Then you need to do something about the blower motor (see page HA-104 in the SR20 FSM).

Sorry for the misinformation. Let us know how it goes.

[zerooath]

nice write up man and statik i think im in love with your car!

[Bandwagon240sx]

Yeah I'll let you know how it goes for sure. I'm not sure what you mean by Russ's comment you quoted though. If the subharness connects to the main harness, if you were to cut the main harness with the leads to the subharness wouldn't you still have to splice into the USDM main harness? Basically no matter what you have to cut and splice it just depends on where you do it. Is that correct? I have no problem doing the cut and splice method like you did though. In all honesty that might be easier than trying to make the jdm subharness work. To me it looks like a larger version of a custom stereo install. You wouldn't hapeen to have an online resource for the SR20 FSM would you? or even a scan of the pages you mentioned?

[projectRDM]

I'll detail it better, since you guys keep talking about me.

Basically what I did and suggested in my old writeup as well as numerous posts since is this:

Take the JDM dash harness out of the clip and lay it all out, unwrapped and without any tape. Trace all the plugs you'll need for the climate control and tape them off. Everything will tie in together except for the few leads that aren't used in the US harness. In most cases you'll find other wiring running through some of the harness you'll need (cluster, radio, etc), just cut those until you've got the entire climate control harness separated from the rest of the dash harness. You'll then only need to cut the illumination lead (black on JDM, but it goes to red/yellow in the US), orange/green (+12V constant lead) , and the two large blue/whites for the blower motor that go to the control head, thus removing it entirely from the dash harness. You now have a subharness that will plug in to all the existing motors and the added sensors, with no rewiring except for the additional ones mentioned above. Leave all the US plugs alone and tape them up in the harness.

While that sounds completely logical to me, if anyone has questions go ahead and ask and I'll try to be more remedial with my explanation.