AC wiring issues
08-05-2015, 12:32 AM
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AC wiring issues 02 LS1, M6, working on getting AC setup and going. I've got a 12v signal going to pin 17 of the red connector.
For the AC pressure switch, I have an 80k ohm 1/4 watt resistor connecting pins the grey and red/black wires on the pressure switch, dropping the 5V reference down to 2V such that pin 14 of the red connector is getting the 2V signal.
With all that, pin 43 is not switching (I'm assuming, from the schematic I'm seeing, it's supposed to switch to a ground). I'm not sure if there is something I am explicitly missing, or if there is another wire I need to look at as well.
One question I did have as well, which might be the whole reasoning for this but is not what I am used to from past cars (and might be a stupid question): Will the AC clutch engage with the ignition to ON, without the engine being on. The schematic says the power supply is hot in RUN or START which, I believe, should be hot when the ignition is in the ON position, but I just wanted to be certain before I try and throw everything together just to test something that is not relevant.
For the AC pressure switch, I have an 80k ohm 1/4 watt resistor connecting pins the grey and red/black wires on the pressure switch, dropping the 5V reference down to 2V such that pin 14 of the red connector is getting the 2V signal.
With all that, pin 43 is not switching (I'm assuming, from the schematic I'm seeing, it's supposed to switch to a ground). I'm not sure if there is something I am explicitly missing, or if there is another wire I need to look at as well.
One question I did have as well, which might be the whole reasoning for this but is not what I am used to from past cars (and might be a stupid question): Will the AC clutch engage with the ignition to ON, without the engine being on. The schematic says the power supply is hot in RUN or START which, I believe, should be hot when the ignition is in the ON position, but I just wanted to be certain before I try and throw everything together just to test something that is not relevant.
08-05-2015, 11:41 AM
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Bump, confirmed that car on or off does not seem to matter. 12v to pin 17 nets me nothing from pin 43. I want to say it was putting out ~8.3k ohms / 0v regardless of the voltage on pin 17.
08-05-2015, 12:57 PM
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Another update...I wired everything up as it would be with the ac clutch relay switch connected to a relay. Pressed the AC button and nothing, so I manually grounded the relay and could hear the compressor click over.
So, this tells me that the wiring *to* the compressor is good, at least. I would assume the wiring to the PCM is good because it simply needs that 12v on pin 17 and the pressure sensor signal (2v) on pin 14.
One thing I did note is that, looking at my the monitor status in an OBD2 reader, it shows AC Refrigerant monitor is not available. I don't know if the LS1 actually has an AC Refrigerant monitor so it might not be important, but I have noted I'm not getting any DTCs for anything related to AC. I would figure (hope) that if something were wrong, it would put out a DTC of some sort.
So, this tells me that the wiring *to* the compressor is good, at least. I would assume the wiring to the PCM is good because it simply needs that 12v on pin 17 and the pressure sensor signal (2v) on pin 14.
One thing I did note is that, looking at my the monitor status in an OBD2 reader, it shows AC Refrigerant monitor is not available. I don't know if the LS1 actually has an AC Refrigerant monitor so it might not be important, but I have noted I'm not getting any DTCs for anything related to AC. I would figure (hope) that if something were wrong, it would put out a DTC of some sort.
08-09-2015, 12:07 AM
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So, anybody that has been following this, somebody experienced with HPTuners came over and looked over everything. Got a confirmation that wiring looked fine so we connected it up to HPTuners and tried to manually trigger the AC Clutch and....nothing. Swapped in an PCM he has, doing nothing with the wiring, and he was able to trigger the AC Clutch fine.
So, apparently, something is up in my PCM that is preventing it from triggering the AC Clutch. We were both equally confused. I guess at this point I'm getting another PCM.
So, apparently, something is up in my PCM that is preventing it from triggering the AC Clutch. We were both equally confused. I guess at this point I'm getting another PCM.