megamax

iTrader: (9)

Iam stumpped here people. iam thinking i have a cross between a mechanical problem and a wiring problem(both or one or the other).

heres the facts

-i didn't swap out the conditioner

-i did replace the condensor and lines from a junkyard car from a 300 of the same year.

-i replaced the ac condensor with a brand new unit(the one under the dash).

-iam using a soarer ecu on a sc400 swap if that matters

-i thought this was the recharge port and i used 1 full can of freon here along with half a can of red dye to check for leaks




-then i found this port never used it before.




-i tested the compress clutch and it does kick on when it gets power.





-iam gettting 12 volts to my clutch control pin.(#5) from the engine side of the harness






I brought the resistor that was mentioned on another thread on here




When i ground the a/c clutch wire (#5) then the clutch kicks on.




so iam stumpped, any takers here?? when i ground #20 wire(ground to the ecu pin) it appears my idle smooths out. iam thinking of using this a permanent ground.

soarer13oy

iTrader: (13)

The ecu sends a ground signal(acmg) to the a/c relay. That completes the circuit and allows the relay to send the 12v to turn on the clutch. Check to see if the ecu is sending a ground from the acmg pin on the ecu.

megamax

iTrader: (9)

what the heck is this acgm you speak of?? the only a/c related pins on the ecu are the clutch #5 and the idle up #20.

Ali SC3

iTrader: (10)

the clutch pin is the one he is talking about most likely that turns the compressor on. when the a/c is on the idle up also gets grounded so the iacv will idle up some, if you ground 20 without 5 you will probably get idle up and no a/c hence the smoothing out of your idle. sounds like its working if the compressor is coming on. what happens after it comes on, no cold air?

megamax

iTrader: (9)

oh, in that case, no. the ecu is getting a constant 12 volt going to the ecu on pin #5.

soarer13oy

iTrader: (13)

The ecu should be sending a ground signal from your pin 5 to the ac relay so your ac can turn on.

GoCarSc300

iTrader: (1)

I just recently took my car to the shop as I'm not as well versed in the electrical aspects as you guys and after a whole lot of diagnostics they determined that I would need to replace my A/C ECM. Its not sending out the ground signal for the A/C relay. They attempted a bypass but it didn't work and the only other option they said would eventually melt the wire due to the increased volatge.

Not sure if that's the problem you're having, but I though my situation may help in some regard. Also, I have a question. If my IACV is unplugged and compensated for with my AEM EMS, could that affect the issue I am having with the A/C not working? It blows air but its not cold and has been recharged and determined to be holding pressure without evidence of leaking.

Any help would be appreciated. I'm trying to figure out if I should go ahead and find an A/C ECM unit to replace mine with or if the IACV being unplugged is ultimately the issue. Thanks in advance!

soarer13oy

iTrader: (13)

The ac ecm sends a ground signal to the ecu, which then sends the ground to the ac relay. Since you have a aem ems, have you confimed that the ems ac has been set up?

I highly doubt your iacv being unplugged has anything to do with the ac not working.

megamax

iTrader: (9)

so after getting some sleep and thinking about this. it is NOT my ac ecu, because it was working just fine right before the swap. so aim guessing not using the a/c up untill now wouldn't make it not work.

megamax

iTrader: (9)

so since this is not happening, then this blue relay i brought should fix the problem then right??

soarer13oy

iTrader: (13)

Yes it should. Check pin number 5 with a volt meter after you have installed the relay to see if the ecu is sending the ground signal.

1JZPWRD

iTrader: (59)

Jim, did you get it to work?

megamax

iTrader: (9)

no, i didn't install the relay. need guidance on the exact wires to splice??

megamax

iTrader: (9)

hey guys!!! which wires do I splice into this resistor??