I’m asking this same question on HT, but I have only gotten one response on there, and I was hoping I would have some more assistance here. So I’ll update you on my problem and what I have found out so far.
When I got my car it did not have any of the AC piping, AC harness, AC compressor, AC condenser, drier, 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 refrigerant.
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
Next:
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.
Next: The helpful response from ‘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"
Last: (Recent)
-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.
-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.
