How to make AC work with your swap, aka: Need help with AC wiring thread Options

[lagos]

ok... so my AC hasnt worked since the swap and i figure now is a good time to wire that crap up. so i have my harness apart and im trying to look at the wiring diagrams to figure out a few things. seems like i need some help.

"ac amplifier" in the diagrams means the main AC compressor, correct?

on it, is a plug called A8 (looking at the 5sfe diagrams). the harness goes from there to a plug called IM1 and then 3 wires go to the ECU's 1st plug. where is IM1 located ? is it the white, 5 wire plug that goes from the 3s hanress, and plugs in right behind the glove box?

This post has been edited by lagos: Jul 29, 2006 - 9:02 PM

[lagos]

i finally found my wiring book. IM1 seems to be the correct plug that i was looking for.

dustin corrected me by telling me the AC amplifier is a large unit behind the glove box and not the main ac compressor that bolts to the motor.

after looking around some more... i belive the AC compressor is labled as "A/C magnetic clutch". and it the harness plug on it is called A2. can anyone verify this?

[MaskedMan]

I think the plug is called A4 (A/C magnetic clutch and compressor sensor) should have 4 wires, and is a grey connector.

[lagos]

yeah, your right. on a 6th gen they call it A2 and on a 3s harness its called A4. thanks for clearing that up.

now.... here is my next qestion. if you were to take the 3sgte harness apart...and trace the wires coming from the a4 plug. where would they all end up?

for example... plug a4, pin 4 is a blac/white wire . this is the main power wire that engages the AC cluch. in the 6th gen, this goes to the main fuse box plug EA1 pin 10. where does it normally go on the 3sgte? im guessing it would go to one of the 2a,2b,2c fuse box plugs that used to be part of the original harness, but what one and what pin. and what about the rest of the 4 wires? where do they get routed to on the original 3s harness?

i cant find any 3s wiring diagrams that have the AC system in them. my book dosnt even metion the AC.... odd.

[lagos]

ok ... i think i figured most of it out...

on the 3s harness they go from:
a4 plug on the compressor.... 3of the 4 wirles go through the fire wall to a plug called IH1 and plug behind the glove box. but that plug wont work for our car, so we have to rewire the IM1 plug in.

and the 4th black wire on A4 goes to one of the fuse box plugs?

This post has been edited by lagos: Jul 18, 2006 - 4:32 AM

[MaskedMan]

well the Black-White wire from A4 goes to a splice point. one end goes to grey connector E7 pin 10. the other end goes up to another splice point. one goes to A/C magnetic clutch relay pin 1. and then other end goes to A/C condenser fan relay NO.3 pin 2. Those are both located in the relay box 5.

the Yellow-Black wire from connector A4 goes to a connector called IH1, pin 3, from there it goes to A/C amplifier connector A17 pin 5.

the White-Blue wire goes to the connector IH1 pin 5, from there, it goes to connector A17 pin 9.

The White-Red wire goes to IH1 pin 4. then to a splice point. one end goes to A17 pin 14. The other end goes to A26 pin 1. this is a 4 pin connector. A/C Thermistor

Pin 2 of A26 goes to A17 pin 16 and is a Yellow-Green wire.

Pin 3 of A26 is a yellow wire, and goes to connector IJ1 pin 5. from there it goes to a splice point. It then splits off and both end connect to other splice points.

I will describe one first..

one side leads to another splice point and then goes to A/C room temp sensor A23 pin 2. then A23 pin 1 is a White-Red wire and goes to connector IQ1 pin 7, then goes to AUTO A/C AMPLIFIER A34, pin 5. the other splice goes to connector EA1 pin 5, which then leads to A/C ambient air temp sensor A1, pin 1. then Pin 2 of A1 is a Yellow-black wire. it goes to connector EA1 pin 4, and then to connector IQ1 pin 1, and from there goes to AUTO A/C AMPLIFIER A34 pin 6.

OK now here is the second one....

Goes to connector IQ1 pin 2, and then goes to splice point I11 where it goes 3 ways. One way is a purple-white wire, that goes to A34 pin 15. Another purple-white wire goes to connector IQ4 pin 14, from there goes to A/C control assembly connector A18 pin 7. (this is a 25 pin connector)

The splice point I11 also has another yellow wire that lead to another splice. The yellow wire then goes to AIR MIX CONTROL SERVO MOTOR, A29 pin 3. (this is a 6 pin connector.) the other wire coming from this splice point is a Orange-black wire. This goes to the A/C water temp sensor A27 pin 3 (this is 4 pin connector). Then pin 1 is a Red-Green wire that goes to connector A34 pin 20 (Auto A/C Amplifier)

and thats it i think.. unless you want to know how the Air Mix Control Servo Motor A29 is hooked up.

This post has been edited by MaskedMan: Jul 18, 2006 - 4:36 AM

[lagos]

awesome! airconditioned car, here i come! haha

now, one more question, just so that i can doubble check everything to make sure the colors didnt change from 5th gen to 6th gen. can you tell me the function of each of the 4 wires coming off the AC compressor? i know the black/white one, but im not sure about the rest.


Black-White = ac magnetic clutch power
Yellow-Black = ?
White-Blue = ?
White-Red = ?

[MaskedMan]

oh sorry i forgot to put where the 4th pin of the A/C thermistor A26 goes. its a green-red wire that leads to connecter IJ1 pin 6 (18 pin connector) then leads to Connector IQ3 pin 3 (8 pin connector) and then it leads to pin 19 of A34 (auto a/c amplifier)

As for what those wires do exactly... ill have to find that out. all i know is that the both the white-blue wire and the white-red wire should have continuity with a/c switch (a/c control assembly) on and ignition sw at on position. I will see what else i can find out.

[lagos]

awesome, you rock

[lagos]

chrisD from ctech was able to hook me up with the diagrams for the alltracs AC system!

http://www.celicatech.com/vfewdsou/1990/90.../ATmaairpus.pdf

[MaskedMan]

oo nice, I was just going off my own alltrac, and the difference from my alltrac and that diagram right there is that mine has Auto Air Conditioner push type control, and that diagram is for a Manual Air Conditioner push type control. I wasn't sure which one you wanted since the 6gc is manual, and the Alltrac is auto (but idk if all alltracs were auto). Just to point out a difference in EWDs There is also Auto Dial type control, and Manual Dial type control EWD. So i was kinda confused on which to use, but now you have a lot of information to go by

[lagos]

alright.... one more quick question. seems the AC wiring has changed in 90. 95 and 98 in the celica . why? who the hell knows.

the AC has a plug (A4) with 4 wires on it.
pin numbe 3's function is labled as "VC" . what does this DO? whats its function inside the AC compressor?

the reason why i ask, is that in a 95 celica, you would hook this up to plug IM1 pin 3, and the it would go to the AC AMP. problem is, this they removed this pin from the 98 IM1 plug and its function (MGV?) dosnt seem to exist on the AC amp! im guessing i can just skip this wire... but i want to know what it does, before i eliminate it.

This post has been edited by lagos: Jul 18, 2006 - 9:08 PM

[MaskedMan]

hmm... ok 2 wires should be to activate the magnetic clutch. And im guess the 2 other wires are sensors? I know there's this one sensor that reads if the compressor is spinning. This will help protect the compressor if there is something cuasing the compressor to be stuck.. But the thing i dont know, is if it's on your car, cuase they did eliminate this later on. Hmm, ill try to find out the name of this, cuase i can't remember, but i'll prolly have time, since my flight is going to be crazy delayed. stupid LAX airport has no electricity.

This post has been edited by MaskedMan: Jul 18, 2006 - 9:18 PM

[lagos]

cool ... if you find out all the functions of the 4 pins on the AC unit, let me know. i like to know what is doing what and why.

now for some good news. everything should be wired up and "in theory", i should have AC again (after i get the system blead and recharged).

i lucked out, because i kept my 5sfe compressor, instead of the 3sgte one. i unpluged the 4 wire plug from it and looked at the pins..... only 3 pins!!! so whatever function they removed from my 98 ac amp, is also not in compressor, so i shouldnt have any issues there. tomorrow, ill plug everything back in and run some tests with the multi meter to make sure everything is wired up correctly. then ill take the car in for a recharge.

on a related topic... man this weather sucks. i couldnt work on the car at all during the day because of the 100+ deg weather. so i wait till night time, and as soon as i get in the garage, we get this huge thunderstorm...lol . i have all this little stuff i want to do before the meet but at this pace, i dont know how much ill be able to get done.

next project is to figure out why my ABS stoped working after the swap.

[MaskedMan]

OOO nice, your 98 compressor should be better anyways. . ill try to figure out what does what when i get home. Is it really that hot up in the EC right now? wow, i remembered it being cooler than here in Cali haha. Haha i think im going to fall asleep at the airport. haha i was up all night looking at the Celica EWDs hahaha. It would be nice for you to have A/C again, A/C is nice, i should be getting my A/C certificate or whatever sometime soon, so i can legaly work on A/C systems , it's just that the course went by so fast, we didn't get to cover wiring much, just mainly the mechanics of it and how to service it. Ugh i just wanna get back home already, haha all this waiting and not being able to work on my car is like killing me haha. Goodluck with your A/C, if you use your stock compressor, cant you just hook everything up the way it says to hook it up in that 6th gen celica EWD?

[lagos]

if you use your stock compressor, cant you just hook everything up the way it says to hook it up in that 6th gen celica EWD?

thats the basic idea.... but you are now using a 1990 3sgte harness. so you have to rewire where the AC gets its power from to engage the magnetic clutch , comunicates with the AMP, and then rewire the signals the AMP gets from your 3sgte ecu (Ac1, ACT, and imput from your ignitor).

This post has been edited by lagos: Jul 18, 2006 - 10:45 PM

[lagos]

ok.. i figured out the functions of the 3 wires that go to the AC unit

pin 1 =SSR+
pin 2 =SSR-
pin 3 = MISSING n/a
pin 4 = MG+


ssr + and - and the speed sensor that only allows the AC compressor to turn on when it detects that the Ac compressor is spining. like you said above, this is a safety feature to make sure the magnetic clutch wont engage if the drive belt breaks or something.

MG+ is the main power for the magnetic clutch.

edit: i doubt anyone else cares about this thread, but this should be some good info if anyone finds it in the futue.

This post has been edited by lagos: Jul 19, 2006 - 1:19 AM

[MaskedMan]

haha nice, i was just about to give you the same info haha. cuase i was reading the Celica EWD on the plane, and i read that PIN 3 was excluded on the 5sfe. I hope you get your A/C working soon! Oh and i read about the ABS as well and yeah, your going to have fun with that haha.

[WannabeGT4]

edit: i doubt anyone else cares about this thread, but this should be some good info if anyone finds it in the futue.

I care. Especially since the last few days have been 105+ I will not be going without AC once my swap is done.

[phattyduck]

I'm also curious as to why there was any rewiring of the A/C system?

For my swap, I left all my A/C wiring stock (along with keeping the stock compressor). At that point, all you need to wire up are the couple wires that go to/from the ECU related to A/C idle up and A/C cut...

Without even hooking those wires up, I get A/C - just no idle up (I only use it on the freeway at the moment) and no A/C cut (turn it off before full throttle).

I looked into swapping over to all ST205 stuff, but putting together that mish-mash of parts and wiring looked like it was going to be hell.

-Charlie

[lagos]

I'm also curious as to why there was any rewiring of the A/C system?

For my swap, I left all my A/C wiring stock (along with keeping the stock compressor). At that point, all you need to wire up are the couple wires that go to/from the ECU related to A/C idle up and A/C cut...

Without even hooking those wires up, I get A/C - just no idle up (I only use it on the freeway at the moment) and no A/C cut (turn it off before full throttle).

I looked into swapping over to all ST205 stuff, but putting together that mish-mash of parts and wiring looked like it was going to be hell.

-Charlie

do you have an st205 swap? if you do, then all your AC stuff probably just plugs in without having to rewire anything.

for the st185, you have to rewire a few things. its about 5-6 wires total that you need to rewire to make it work. its pretty easy.

[phattyduck]

do you have an st205 swap? if you do, then all your AC stuff probably just plugs in without having to rewire anything.

for the st185, you have to rewire a few things. its about 5-6 wires total that you need to rewire to make it work. its pretty easy.

Yup, ST205 - but into a '90 Camry... So no, nothing plugs in between the two A/C systems.

My clip had auto A/C and RHD, so some of the stuff probably would have been different anyway.

I left everything A/C related except the two wires to the ECU original. My only issue is that the ST205 ECU has 3 wires to the A/C system, and none of the pin names match up...

Either way though - it sounds like you have a decent plan of attack for your A/C system.

-Charlie

[lagos]

so i put everything back togther today to test out the ac but it dosnt seem to be working!?!

i start the car, turn the AC on, but i dont hear the radiator fans spin up or anything?

i checked for continuity from the black/white plug on the ac compressor to EA1 pin 10 and it IS there. then i checked for continuity from EA1 (male) pin 10 to the AC Rlay pin 3, and it is aslo there. so i dont understand why the AC and/or fans are not kicking on.

i disconnected the AC lines during my swap so the lines were empty. i tired to refill it with a can of r134 just to see if i would get any ac. i filled it to about 35psi... but still nothing.

any ideas?

[lagos]

"Pressure Switch
The pressure switch is threaded into the liquid line. It
sends a signal to the A/C amplifier to inhibit compressor operation
whenever high side pressure is too high or too low. "


seems there is a factory "kill switch" if your AC lines are too low or over filled. mybe this is my issue?

[MaskedMan]

maybe. this is becuase the oil, is mixed in with the refridgerant. If there is low refridgerant, then the compressor will not operate. Cuase the system will not turn on to protect the compressor against seizing up.

[lagos]

yeah... i think this is whats going on.

i traced the power routing for the whole ac system. it goes right from the AC fuse, to that presure switch on the AC lines. then the power goes to the AC amp. the sensor also has 2 more lines that are tied into the Fan relays. if i unplug the sensor, the fans go into their fail safe operation and stay on all times.

also, when i press the AC button ON, the sensor gets power to the wire that it should. so i think everything is wired up right. i think the wiring is right, i just need to get it recharged. i can also jump the 2 wires in that sensor and see if my AC clutch kicks in, to test things out even more if i want, but i dont know how safe it is to engage the AC clutch without any gas in there....

[Dr_Tweak]

You could do it for a couple seconds okay, just don't leave it running.

[lagos]

You could do it for a couple seconds okay, just don't leave it running.

if i take the time to type out how i wired everything up, can you doubble check it for me ? i want to make sure i didnt miss anything, before i go pay a shop to recharge it.

[lagos]

plug IM1 (female) 6th gen plug that goes behind the glove box.

(pin) (where i wired it to) (what it does)

pin1 = ecu plug E8 A- pin 21 = ACT function in the ecu
pin2 = ecu plug E8A - pin 10 = AC1 funtion on the ecu
pin3 = doesn not exist on 98 harness
pin4 = st185 plug IH1 - pin 4 = this leads to the white/red wire on the AC
pin4 = st185 plug IH1 - pin 5 = this leands to the white/blue on the AC
pin 6 = II1 pin 3 = this is the tach signal from the ignitor


PLUG 2c from the ST185 harness

pin6 = EA1, fuse box plug- pin 10 = this comes from the black/white power line for the AC clutch that is on the AC compressor


i THINK thats it.

[Dr_Tweak]

Just off the top of my head, it does look like you have everything correct. Really the most important thing is the a/c clutch circut, if that works then your a/c will work. Then we just need to make sure your engine idles up when it comes on. What year is your ECU?

-

*edit* Oh yeah, and you can pick up one of those little cans at Wal-mart or Pep Boys or whereever and fill it yourself. It's really easy, the instructions are on the can and it'll save you like $100.

-Doc

This post has been edited by Dr_Tweak: Jul 21, 2006 - 10:33 AM

[lagos]

Just off the top of my head, it does look like you have everything correct. Really the most important thing is the a/c clutch circut, if that works then your a/c will work. Then we just need to make sure your engine idles up when it comes on. What year is your ECU?

-

*edit* Oh yeah, and you can pick up one of those little cans at Wal-mart or Pep Boys or whereever and fill it yourself. It's really easy, the instructions are on the can and it'll save you like $100.

-Doc

the ecu is a 1990.

i have a bottle of 134. problem is , that i the AC lines were disconnected and there is air in the system. so i need to take it to a shop so that they can put it on an electric vac pump to bleed everything out before i can refill

[Dr_Tweak]

You don't actually *have* to have it vacuumed. I would give it a shot before taking it in.

-Doc

[WannabeGT4]

You don't actually *have* to have it vacuumed if you don't mind replacing the seals and/or compressor in a year or two. I would give it a shot before taking it in.

-Doc

Fixed.

[lagos]

IT WORKS!


i got another bottle of R134 because the one i was using was a few years old, and the gauge on it didint really sit at 0. so the whole time i thought i was over inflating it, when in fact i still had a lot of room to go. once the sensor saw there was enought psi in the system, it kicked the fans on and the AC relay. so now the AC works!

only problem is, that its not really as cold as it should be. so im still going to take it in and have it purged anyway, and refill it again. at least i got to learn all about my AC system while doing it...hahaha

[Fastbird]

Lagos, with everything working, does your car idle up when the A/C is turned on??

[lagos]

Lagos, with everything working, does your car idle up when the A/C is turned on??

no.

i have to install the idle up valve that does that. i think its somwhere in my basement. then i have to see how to wire that up and run some vac lines to it. its not a big deal tho, because the car dosnt stall out or anything, just idles a little less then it should.

This post has been edited by lagos: Jul 21, 2006 - 5:10 PM

[lagos]

i did a little ghetto bleeding . fill the low side while venting the high side. it did the trick and now the AC blows ICE COLD ! its so great driving around in a turbo car will all the comforts of a daily driver.

does anyone know the exact PSI our system should be filled to? i did mine to about 35psi.

[Aaagogo]

so this will be the working wiring configuration

plug IM1 (female) 6th gen plug that goes behind the glove box.

(pin) (where i wired it to) (what it does)

pin1 = ecu plug E8 A- pin 21 = ACT function in the ecu
pin2 = ecu plug E8A - pin 10 = AC1 funtion on the ecu
pin3 = doesn not exist on 98 harness
pin4 = st185 plug IH1 - pin 4 = this leads to the white/red wire on the AC
pin4 = st185 plug IH1 - pin 5 = this leands to the white/blue on the AC
pin 6 = II1 pin 3 = this is the tach signal from the ignitor


PLUG 2c from the ST185 harness

pin6 = EA1, fuse box plug- pin 10 = this comes from the black/white power line for the AC clutch that is on the AC compressor


i THINK thats it.

[lagos]

yep thats how you wire it up.

you just need to look up the plug names so that you know what and where they are. all that stuff is in the toyota wiring diagram books.

[MaskedMan]

does anyone know the exact PSI our system should be filled to? i did mine to about 35psi.

The low side pressure should be 21-35psi, and the high side pressure should be 190-220psi.

[lagos]

whats the deal with the AC idle up valve? i see it in the wiring diagrams for the 5th gen setup, but it dosnt exist in any of the 6th gen wiring diagrams. did toyota change the way the AC idles up in the 6th gen?

[WannabeGT4]

http://www.celicatech.com/vfewdsou/1995/95...ic/engcon5s.pdf


Unless something changed from '95 to '99 then:
plug E5 pin 7 "ISCV" on the 5SFE ECU controls the A/C idle up VSV.

plug E5 pin 21 "ISC" on the auto 7AFE ECU controls the A/C idle up VSV.
plug E5 pin 23 "ISC" on the manual 7AFE ECU controls the A/C idle up VSV.

[lagos]

ah ha! nice find.

i was looking at the AC specific diagrams and wondering why it wasnt there.

so it seams like there is a problem with adding AC idle up. on the 3sgte the idle up control is done by the AC amp.

in the 6th gen the AC amp dosnt have this function, because it is handled by the ECU.

so it seems there is no way to do it the way it is from the factory.

since the Idle up, only gets triggered when the AC clutch engages, i was thinking that maybe i can get it to work by splicing into the blac/white wire that supplies power to engage the cltuch on the AC compressor. this way, every time the clutch would come on (and make the rpm's dip down) the AC idle up would get 12v, and open its vac ports and make the car idle up. what do you guys think?

[Dr_Tweak]

ah ha! nice find.

i was looking at the AC specific diagrams and wondering why it wasnt there.

so it seams like there is a problem with adding AC idle up. on the 3sgte the idle up control is done by the AC amp.

in the 6th gen the AC amp dosnt have this function, because it is handled by the ECU.

so it seems there is no way to do it the way it is from the factory.

since the Idle up, only gets triggered when the AC clutch engages, i was thinking that maybe i can get it to work by splicing into the blac/white wire that supplies power to engage the cltuch on the AC compressor. this way, every time the clutch would come on (and make the rpm's dip down) the AC idle up would get 12v, and open its vac ports and make the car idle up. what do you guys think?

Yes, that's exactly right. The best thing to do is actually have the clutch wire go through a relay, and have the relay switch on a VSV. The only downside to this is that it will be on all the time, even when you're not at idle. It will work though, just make sure that one side of the VSV goes to the manifold and the other side goes to the intake behind the AFM.

Good job putting it together and congrats!

-Doc

This post has been edited by Dr_Tweak: Jul 22, 2006 - 6:12 AM

[WannabeGT4]

Couldn't you use the IDL signal from the TPS to prevent the VSV from opening when ever you're not at idle? It might be more trouble than it's worth but I don't see why it wouldn't work.

[presure2]

Art,
great to see you tackle this project and work it all out.
added to the sticky!
=)

[lagos]

ah ha! nice find.

i was looking at the AC specific diagrams and wondering why it wasnt there.

so it seams like there is a problem with adding AC idle up. on the 3sgte the idle up control is done by the AC amp.

in the 6th gen the AC amp dosnt have this function, because it is handled by the ECU.

so it seems there is no way to do it the way it is from the factory.

since the Idle up, only gets triggered when the AC clutch engages, i was thinking that maybe i can get it to work by splicing into the blac/white wire that supplies power to engage the cltuch on the AC compressor. this way, every time the clutch would come on (and make the rpm's dip down) the AC idle up would get 12v, and open its vac ports and make the car idle up. what do you guys think?

Yes, that's exactly right. The best thing to do is actually have the clutch wire go through a relay, and have the relay switch on a VSV. The only downside to this is that it will be on all the time, even when you're not at idle. It will work though, just make sure that one side of the VSV goes to the manifold and the other side goes to the intake behind the AFM.

Good job putting it together and congrats!

-Doc

no relay needed! and it wouldnt be on all the time. the AC clutch gets cycled on and off ever few minutes by the evap temp sensor. it dosnt stay on all the time. so 12v comes on and off to the clutch on the AC comp, while you have your AC on in the car . by simply splicing into that wire, the car would idle up at the same exact time the cluch kicks in, and idle back down to normal, when the evap sesnor cycles the clutch off. if your ac was off, then the car would act normal because the clutch idle up wouldnt be getting any voltage.

EDIT: ah i get what your saying. the Vsv would also engage while you are driving. i wonder how much this would really effect the car while its driving. since the AC comp only makes the motor idle at about 50rpm less then normal when at idle.

This post has been edited by lagos: Jul 22, 2006 - 9:18 AM

[WannabeGT4]

Like I said use the IDL signal from the TPS to trigger a relay that is powered by the AC magnetic clutch signal. That way the VSV will only come on under two conditions, 1. you're at idle and 2. your compressor clutch is engaged.

[lagos]

yeah, your right, that would probably be the best way to do it.

do you know what kind of voltage the IDL singnal sends out at idle?

[lagos]

i thought of another simple way of doing this. the basic problem is that with the AC on, the car idles too low. so you can also add the idle up in, simply by taping into any wire that gets 12v when the AC BUTTON (not clutch) is pressed. a good place for this would be to tap the purple wire that goes to the presure switch. this will make the car idle at something like 900 rpm, instead of the normal 800, and when the ac clutch comes on, it will only dip down to 850rpm and not the 700ish that makes the car idle crappy.

this way, you wont have any issues if the system making the rpm's jump up on their own while you are driving, and you wont have to mess with the TPS singal or use a relay.

[WannabeGT4]

The whole purpose of the idle up VSV is to stabilize the idle when the clutch is engaged and there is an extra load on the engine. As you already pointed out, having the VSV engaged whenever the AC button is pressed will still cause a fluctuation in idle since the clutch is not constantly engaged when the AC button is pushed. A single relay triggered by the IDL signal to engage the VSV which is also powered by the AC magnetic clutch wire is probably you're best bet.

[lagos]

The whole purpose of the idle up VSV is to stabilize the idle when the clutch is engaged and there is an extra load on the engine. As you already pointed out, having the VSV engaged whenever the AC button is pressed will still cause a fluctuation in idle since the clutch is not constantly engaged when the AC button is pushed. A single relay triggered by the IDL signal to engage the VSV which is also powered by the AC magnetic clutch wire is probably you're best bet.

yeah, your right. that is the best way to do it.

im going to try a really simple idle up, first and see how i like it. the idle only really dips down by about 50rpm when the AC kicks on. so i dont think ill have to go through taping into the tps idle signall with a relay, to get it to do what i want. i also have feeling that even if you add the relay, its going to take second for the tps to send out and idle signal ,and the relay to click on, and it will never be a super smooth and perfect setup. even on a bone stock car, the idle is never 100% pefrect when the ac is on.

[Dr_Tweak]

Like I said use the IDL signal from the TPS to trigger a relay that is powered by the AC magnetic clutch signal. That way the VSV will only come on under two conditions, 1. you're at idle and 2. your compressor clutch is engaged.

That's a great idea.

-Doc

[lagos]

so here is an update....

i added in the AC idle up system and it works great. all i did was tap into the black/white wire from the ac compressor, and ran that right to the AC vsv and from the vsv to ground. it ended up working very well.

i also noticed a benefit for doing it this way vs an idle relay. before without the idle up system, if i turned the ac on while driving, i would feel a loss in power from the engine. now with the vsv working at all times, i no longer feel the drop in power. also the car seems to have about the same power with the ac on as it does with it off.

This post has been edited by lagos: Jul 29, 2006 - 8:40 PM

[phattyduck]

so here is an update....

i added in the AC idle up system and it works great. all i did was tap into the black/white wire from the ac compressor, and ran that right to the AC vsv and from the vsv to ground. it ended up working very well.

That's a really good idea! Just make sure you turn off the A/C before you do any crazy full-throttle driving. You don't want to over-speed the compressor.

-Charlie

[lagos]

so here is an update....

i added in the AC idle up system and it works great. all i did was tap into the black/white wire from the ac compressor, and ran that right to the AC vsv and from the vsv to ground. it ended up working very well.

That's a really good idea! Just make sure you turn off the A/C before you do any crazy full-throttle driving. You don't want to over-speed the compressor.

-Charlie

i dont think that would be a problem. the compressor has a speed sensor inside of it that tells the ac amp wants going on. the ac amp also gets a signal from the Tach so it knows what rpms you are at. so im sure there is some type of fail safe inside the ac amp that controls all that stuff.


i have to track down a mystery noise that im hearing. i hear something rattle around when the ac is on. when i put my clutch in, or turn the ac off, the noise goes away. at first i thought maybe my throw out bearing was making noised when the car idled too low, but now thats fixed and its still doing it. maybe the ac belt is too loose. ill have to go check it out.

[malecrod]

Sorry to bring this back from the dead. I have a working AC but no idle up system. I was able to source an idle up unit off of MR2oc. I read through the entire thread and the wiring diagrams. I'm new to all this wiring stuff but I kinda got most of the issues involve in wiring the idle up unit.
My question is: Is splicing into the black/white AC compressor and grounding the other wire the final solution to the AC-on crappy idle issue? I'm about to attempt this and I'm wondering what is the final word on this.
Any help will be appreciated. Thanks.

[lagos]

Sorry to bring this back from the dead. I have a working AC but no idle up system. I was able to source an idle up unit off of MR2oc. I read through the entire thread and the wiring diagrams. I'm new to all this wiring stuff but I kinda got most of the issues involve in wiring the idle up unit.
My question is: Is splicing into the black/white AC compressor and grounding the other wire the final solution to the AC-on crappy idle issue? I'm about to attempt this and I'm wondering what is the final word on this.
Any help will be appreciated. Thanks.

Yes just splice into that black wire, or any wire that gets 12v when you push the AC button on.

[malecrod]

Sorry to bring this back from the dead. I have a working AC but no idle up system. I was able to source an idle up unit off of MR2oc. I read through the entire thread and the wiring diagrams. I'm new to all this wiring stuff but I kinda got most of the issues involve in wiring the idle up unit.
My question is: Is splicing into the black/white AC compressor and grounding the other wire the final solution to the AC-on crappy idle issue? I'm about to attempt this and I'm wondering what is the final word on this.
Any help will be appreciated. Thanks.

Yes just splice into that black wire, or any wire that gets 12v when you push the AC button on.

Alright, thanks Art. I will go ahead and do that. Thanks