Trouble Shooting A/c In R33

[a2z]

Trying to fix my A/C in My wifes R33 GTST but am finding dead ends wherever I look.

I have Checked all relays and continuity of all wiring. I have also ruled out low pressure sensor. The system is holding pressure and the compressor runs and cools the car when I earth the a/c relay or bridge the pressure sensor plug. I have also check the eccu for correct voltage at pin out 46. The only problem I have found is there is no dip in voltage of pin out 9 when the on off switch is activated.

Is There any auto elects out there that have some answers.

Any other ideas would be awesome.

[Moodles2]

http://www.skylinesaustralia.com/forums/topic/410426-r32-climate-control/page__view__findpost__p__6557064

[a2z]

Thanks Moodles I had already read through that topic and have accessed the diagnostic mode. Still no answers.....

[a2z]

I went to 2 auto electricians today. Still no answers. I changed over the pressure switch. I have tried 2 other climate control units and even another ecu. STILL NOT WORKING.

[89CAL]

If you tell everyone what the problem is it will make it easier to help you out

[a2z]

All I know at the moment is; All components check out to be fine. When I switch on the climate control the clutch does not engage on the compressor.

[Dose Pipe Sutututu]

just put another relay in, I had the same issue trying to fix Ph@t-G's foglights & horn, The relays were fine, checked continuity, everything.. then I was like fine I'll just try different relays. Turns out the relays were fried, they couldn't handle the current.

[a2z]

I'll give it a go. I am at a loss as to what else to try. I also tried changing the relays around like you did. So I guess I will buy a newbie and try it. Gees I hope I figure this one out. It's f@$king with my head.

[Dose Pipe Sutututu]

yeah, cheap anyways.. at least you can rule it out.

Like I said, I spent days on Ph@t-g's car, tested the relays, you name it.. then I just swapped them with mine, bingo!

[a2z]

I guess I will just cross that one off the list too. Doesn't seem to want to be fixed. The strange thing is It cools all the relays will work when bypasses are made at varying points. The climate control module is switching correctly and the compressor is working and cooling the car. The only thing is that if there is not an earth to trick the system, nothing runs. Starting to get fricken real annoying.

[Dose Pipe Sutututu]

I guess I will just cross that one off the list too. Doesn't seem to want to be fixed. The strange thing is It cools all the relays will work when bypasses are made at varying points. The climate control module is switching correctly and the compressor is working and cooling the car. The only thing is that if there is not an earth to trick the system, nothing runs. Starting to get fricken real annoying.

hrms, maybe the engine harness is loose? or even the interior loom to engine/ecu harness is loose.. check those connectors.. they should mate into the ecu loom

[a2z]

I thought that too. I went to a wrecker and tried two other ecu's making no change. The other thing I'm thinking of trying is pulling out the the unit under the dash and checking the thernistor. Just about out of ideas. I am thinking that if that resistor is no good the the computer won't allow the a/c to be turned on. Its just a matter of working out what needs to come out to get to it.

[kitto]

Low refrigerant?

[a2z]

Had air con re-gassed. That's when all this started. The system had absolutely no gas in it . But there are no leaks and as I have said before. The compressor runs and cools when earthed. But not when using climate control. It may be taking a while to fix this. But I'm not going to let it beat me. I have had three profesionals look at it so far and I seem to be doing all the research. On the plus side I know how the car is being pulled apart and put back together and not having to pay someone by the hour to be removing a'll the interior bits and pieces is also a save. I'm going to know the r33 pretty well after all this. Lol.

[Dose Pipe Sutututu]

is there a -ve current going to the A/C relay at least? I am guessing here, but have you check the A/C fan relay as well? I would be surprised if the A/C compressor & A/C fan relays are connected in series.

[Dose Pipe Sutututu]

*wouldn't

[kitto]

Have you got yourself a full wiring diagram to follow?

If you do, start at one point and work through the entire wiring system.

A/C Clutch should get a 12V+ current to the wire for the clutch and grounds through the body of the compressor. Shouldn't be a 0VDC current.

[a2z]

I have two different wiring diagrams although they do not show the complete wiring of the a/c components. They do however show the car wiring to relays. They do not show the thermistor or the other sensors or components.

What I have done this evening quickly was look closer at the relay wiring. If I add earth to pin 1 on the compressor relay, while it is plugged in, it closes the circuit. Then the climate control unit will turn the compressor and A/C on and off. The issue now is that the compressor does not cut out when it should. The idle advance drops and raises the idle when the compressor should cycle on and off but the compressors remains on.

[a2z]

Anyone got a wiring diagram just of the a.c. system?

[jjman]

iv had the trouble in my R33 of my ac switching on and the often (but not always) off again after only 5-10 secs of being on (this is in A/C on mode with 18 degrees selected so technically should run indefinately in warm weather as the interior isnt 18degrees before it switches off sometimes). Sometimes it doesnt even switch on.

THo there is no constant situation (like hot or cold ambient) where it runs, is intermittent or doesnt switch on in.

There is plenty of refridgerant as the view glass is nice n green when on and the air is nice and cold.

Iv run the diagnostic mode and no faults.

anybody know what might be the cause of this or experienced it?

otherwise can you access all of the cars sensors via a consult cable and program? im sure that one of the sensors must be shitty and so going outside its operating range quickly and then switching the AC off. Tho its problem doesnt show in diagnostic mode...

Anybody? (i cant go another summer without it working)