monster d

When I got my car it did not have any of the AC piping, AC harness, AC compressor, AC condenser, dried, or the compressor bracket.

I bought all the piping(which came with a drier), new gaskets, new compressor, AC bracket, condenser fan, and went to a junk yard and pulled the AC harness.

I installed everything and tried to charge the system, but my compressor or condenser fan will not kick on. I figured this was because of the pressure being so low, so I jumped the compressor so I could fill the system to the about 2lbs of refridgerant.

I plugged the compressor back up to the factory harness and tried tried to control the AC in the car and nothing was happening.

I do not get a green light on my AC button. So I figured it might have been a bad switch, I took it out and check the continuity of the switch and when I press the switch in. I got continuity for the black and white wires on the switch, these wires connect to the white - blue/red and black - green on the chassis harness.

So next I checked to see if I was getting 12v to the switch, which is the black/yellow wire, and yes I am getting 12v.

So I'm kind stuck now...id really like to get the AC working in this car as soon as as possible, so any help would be awesome

monster d

there are 2 wires from the ecu that goes to the clutch and fan relays. when i ground the 2 leads they both turn on. they are A15(ACC)yellow and B5(ACS)blu/red. so any chances it's my ecu? they each go to #85 on the relay.

I do have a p75 ecu in my car for a 94-95 Acura integra. I don't think that would really make a difference but idk.

fcm

The output from the A/C switch is a ground, [blue/red lead] it gets it's ground from the blower motor switch, [green lead] the switch also supplies the ground for the A/C indicator bulb, 12V+ for the bulb is from fuse 17-7.5A, hot in run[blue lead].

The ground output from the A/C switch runs to the A/C thermostat, [behind glove box].

The output from the A/C thermostat runs to the A/C diode and the ECU, [blue/red].

Output from the ECU, [yellow lead] also a ground, runs to the A/C compressor clutch relay.

Both the rad fan and condenser fans are controlled by the rad fan control unit and A/C diode, [US model, Canadian model does not have a rad fan control unit].

You should be checking for a ground output from all the above components. 94

monster d

Okay so what and where is the AC diode? Same with the rad fan control unit?

I know my rad fan works good.

Soo how exactly should I go about checking the ground outputs? Would I push the button on and see if I'm getting voltage at the thermostat, then if so I move onto the next thing and so on and so forth?

Thanks for the information, been chasing wires all day.

monster d

So I don't know if this is the correct way to do it. But if I'm following you correctly I should be getting a signal from the left blue/red wire on the thermostat ( looking at the at the connector with the clip point up ) when the AC button is pressed in.

So I just probbed that wire with my multimeter, turned the key to (II) and pressed the AC button. Then I took my other lead and put it to a chassis ground and I didn't get any voltage signal. So my question is am I going about this the wrong way or what?

Again thanks for all the help.

fcm

Your looking for a ground, [continuity to chassis ground] not voltage.

Set meter to continuity, setting that "beeps" when probes are touched together.

Turn ign. on and press A/C switch.

First, does A/C indicator light turn on?

If so, check for a ground at the A/C pressure switch, [both leads/ in and out].



If good then check for ground at the A/C thermostat, again on both leads, [in and out].

Both the A/C diode and Rad fan control unit are behind/above drivers kick panel, the diode is taped to the top of the wire harness, two blue/red leads and a yellow/green lead
the RFCU has seven leads going to it. 94

monster d

What if my AC light doesn't come on at all?

monster d

Update:

So AC button still doesn't work when I press it, meaning the light doesn't come on.

I checked fuse 17 and I am getting 12 volts across terminals. Also checked for continuity across the AC pressure switch plug and AC thermostat and got nothing.

How do I got about trouble shooting/fixing the actually AC button. I'm guessing that is my culprit right? Because it is what starts the whole system, which is why I'm not seeing any continuity at the pressure switch and the thermostat correct?

Another question:

Just to be clear, this button should still light up even if my AC system is low on refridgerant correct? Because I'm pretty sure my 92 Integra's A/C system isn't sophisticated enough to not allow the whole system to not function because of low refridgerant. And I feel this is correct because in my other car, a 1991 Honda Civic, my AC button would light up and kick my compressor and condenser fan on even when there was no R12 in the system anymore.

fcm

Yes it should light up even if low on refrigerant.

Do you have power on the blue lead going to the A/C switch, [power for indicator bulb]?

Do you have a ground on the green lead going to the A/C switch, [with blower set at one of the speeds]?

You must have both the ground and power for the bulb to work, you only need the ground for the A/C to work. 94

monster d

I have not checked those wires yet, I will check them when I get home. The ground I can check by doing one lead to the green wire and my other lead to the chassis right?

fcm

Yes on the green ground to the A/C switch. 94

monster d

Okay I checked both of those. I got 12 volt at the blue, and continuity at the Green.

Then my button light started working again immediately after probing from the previous task.

So I went on to test the pressure switch plug and thermostat plug. And I'm still getting nothing there across those.

Then I searched for the diode. After get tired of looking in the driver side, I looked in the passenger and found in on the right side of the kick panel. I'm not sure how to test this one, but I know where it is now. The RFCM was right above the thermostat. Again don't know how I should go about testing these one as well.

After all the probing I did, my AC button light stopped coming on again..lol Soo I'm not sure what the **** to do.

I also was getting contiuity when I checked all the wires in the plug that connects to the AC button.

Still very frustrated and confused.

fcm

No point in checking anything past the A/C pressure switch if your not getting a ground at the pressure switch, it is the next component after the A/C switch.

The A/C switch supplies a ground to the pressure switch, if your not getting the ground at the pressure switch and you are getting a ground out of the A/C switch, look for a break in the blue/red lead running from the A/C switch to the pressure switch.

It sounds like you have an intermittent problem with the A/C switch itself, I would try replacing it. 94

monster d

If you don't mind what is the sequence? AC button, pressure switch, etc? Just for future reference.

Yeah I don't know wtf is wrong with this button or wiring. I have pulled/bought three AC button now from he junkyard. Is there a chassis ground that runs to the AC button that could be loose/cut somewhere that I need to check as well?

Because I know barely any of my climate controls lights work as well.

fcm

Yes there is a ground, [black] going to the climate control, it supplies the ground for the blower motor switch, if the blower motor works then the ground is good.

The blower switch has 4 output that go to the blower resistor for the blower motor it also has a "5th" output that goes to the A/C switch, [green lead].
If the green lead going to the A/C switch, [actually the green connects to a white lead at the switch] has a ground on it when any one of the blower speeds is selected, you should get a ground on the blue/red lead coming from the A/C switch and at the A/C pressure switch, [when A/C switch is on].

When testing you do it is sequence, starting by making sure the switch has a ground going to it and out of it, [when on].

The A/C pressure switch is next in sequence after the A/C switch, [actually the blue/red wire is next in sequence] so if you have a ground out of the A/C switch but not at the A/C pressure switch, [input side] then the problem would be the wire or a connection in the wire.

So you start at the top of the "stream" and test along the way in sequence to find the problem. 94

monster d

Okay here is what I figured out tonight.

First thing first...the lights on my climate control are just FUBAR'd for right now lol..

Second I found out the sequence for the BLU/RED wire goes through after you press the A/C button and turn the fans on:

First - A/C Thermostat (which I got continuity when I was connected to ground...good, next)

Second - A/C Pressure Switch (which I got continuity when I was connected to ground...good, next)

Third - Radiaitor Fan Control Module (which I got continuity when I was connected to ground...good, next)

Then after the RFCM I'm not to sure of. But I got a good idea. I think it sends another signal to the ecu telling it to kick the compressor and/or condenser fan on. With that being said I think I might have found my problem now because on my first day of trouble shooting I grounded the B5 and A15 wires, that came from the ECU to the compressor and condenser fan relays, the compressor and condenser fan kicked on. Which that rules out the relays being bad, which one was bad and luckily I had another laying around.

So what can I do to test the RFCM. I opened it up and all the soldering points looked intack.

fcm

the only reason the RFCM is there, is to run the fans when ign. is off and oil temp is high, it is paralleled with the relays and powers but has an extra input from an oil temp switch.

WE do not have the RFCM or the oil temp switch in the CDM Integra all the rest of the wiring is the same.

Wiring for the RFCM...
1-white/green from oil temp switch, it supplies a ground when oil too hot.
2-white 12V+ from fuse 20- 15A, hot at all times, also power to the clutch and condenser relays.
3- black ground for the RFCM.
4- black/yellow, [yellow/white at RFCM] is 12V+ to the condenser fan relays coil, the one lead that is not paralleled, the CDM Integra condenser fan relays coil gets it's 12V+ directly from fuse 17-7.5A, [hot in run].
5- yellow/black 12V+ to the rad fan relays coil, paralleled from fuse 21-15A, [hot in run]
6- blue/red, paralleled with A/C diode, ground when A/C on to trigger condenser fan relay
7- black/yellow 12V+ for the RFCM, from fuse 24-15A hot in run and start.


The RFCM has nothing to do with the ECU other then the parallel connection of the blue/red lead that runs from the A/C diode to the ECU, as mentioned the CDM Integra does not have the RFCM, [again it's only function is to turn on the fans (condenser fan] when ign. is off and engine oil temp is too hot, and to supply power to the condenser fan relays coil]

To test check for the power and grounds going and coming from the RFCM

1- white/green ground from oil temp switch, will show nothing unless oil is too hot but if you supply it a ground, when ign. is off the condenser fan should turn on.
2- white 12V+ should have 12V on it at all times, [fuse 12].
3- black ground, full continuity to chassis ground.
4- black/yellow-yellow/white 12V+ output from RFCM to the condenser fan relays coil, test this lead at both the RFCM and at the condenser fan relays coil to elliminat an open circuit between the two.
5- yellow/black 12V+ when ign. switch is on.
6- blue/red, ground when A/C on or a ground is supplied to the RFBM white/green.
7- 12V+ when ign. is on.

So I understand, when you say " which I got continuity when I was connected to ground...good, next" are you saying you have a ground at those points?

Also the sequence is A/C switch-A/C pressure switch-A/C thermostat- A/C diode and ECU, [parallel] and last are the rad fan relay and RFCM and condenser fan relay, A/C compressor relay is controlled directly from the ECU. 94

monster d

I'm saying the AC button is pressed, Key is in (II), one lead in the plug, and the other is connected to the chassis ground.

Well my sequence is messed up some how because if I go from the blu/red leading from the AC button to the thermo stat I get continuity. Now if I leave the thermostat unplugged then go from the BLU/red on the AC button to the pressure switch then I get no continuity until I plug the thermostat back in. Then if I follow the wire coming out of the pressure switch it leads to the RFCM, the only other BLU/red that goes back to the AC harness in the engine bay is the one that comes from the Ecu, and that one leads the relays.

Also I'm going to check all those wires when I get home.

fcm

Maybe my manual is wrong, but it really makes no difference what sequence most of it is in as it is all in series anyway. as long as there is a ground at the ECU blue/red and a ground out of the ECU yellow when A/C switch is on, that should turn the compressor on.

For the fans you need to see a ground into the A/C diode, blue/red and out of the Diode blue/red and yellow/green, if you can not access the diode test the blue/red at the condenser fan relay, [may be a blue lead at the relay] the blue/red at the RFCM and the yellow/green at the ECT switch or at the rad fan control relay.

All these points need to be grounds when A/C switch is on. 94 94

monster d

Okay I just tested both blu/red and the yel/grn on the AC diode. All three where getting continuity to chassis ground.

What is a ECT by the way?

Everything checked out for the RFCM.

Okay so for the two relays on the driver side of the engine bay. I am gettting 12 volts in the top parts of the plug on both plugs. One plug has both ground being made and the other has just one ground being made.

Where did you get your diagrams from and where can I get some?

fcm

Diagram is from my Haynes manual.

I believe those would be the condenser fan relay and the compressor clutch relay, [the A/C diode may also be there.

Both relays will have one terminal that is hot at all times, [white lead].
Both relays should have one terminal that is hot when ign. is on, [black/yellow lead].
The condenser relay should have a terminal that goes to ground when A/C switch is on, [blue/red-blue lead]
The compressor clutch relay should have a terminal that goes to ground when engine is running and A/C switch is on, [yellow lead]
The blue/black lead of the condenser fan relay is an output, [12V+] when relay is energized, [on].
The red lead of the compressor clutch relay is an output, [12V+] when relay is energized, [on]. 94

monster d

Thank you! I didn't get a chance to look at the car yet, had a busy weekend. Ill update you after I look at it again, hopefully tomorrow.

But I did finally get a diagram of the AC system wiring. And I'm pretty sure I'm not getting the signal from the yellow wire from the ECM to the condenser relay

fcm

The yellow lead from the ECU/ECM does not go to the condenser relay it goes to the compressor clutch relay. 94

monster d

So I found my problem. My BLU/RED wire going to the ECU had a short somewhere. The BLU/RED that leads out of the pressure switch goes to the ECU and diode. I was getting ground at my diode but not at the ECU. So I jumped a wire from my diode to my BLU/RED on the ECU and boom clutch and condenser fan work great.

Now it's time to get some god damn AC blowing in my car..thanks for the help

fcm

94