P38A Fault code

It occurred to me that I have a compressor lying around from a parts car so I hunted it down and checked it out. Resistance is 4.2 ohms and it draws 3 amps from 12 volts. I could definitely hear a click when connecting it. Resistance would be the easiest thing to check. Hope that helps.

Yer I’m away at work at the moment will try and do them tests the wkend thanks for help

Cheers back home now for some checks can you tell me how you check the ohms on the compressor then because the original fault did say could be open circuit what ever that meens

Just checked it out again why I was standing there with blower on cold the clutch span for a second or two then just stopped don’t know I’ve that makes any sense coz it sure as hell don’t to me

You check the resistance by pulling out the plug and then touching the two multimeter probes to the small pins you see inside the mating part that is on the compressor. First touch the two leads together to see if you are getting 0 ohms as you should$
If the clutch kicked in briefly it is likely good. Did you say you put some gas in? Maybe add a bit more. Also, did you check the connector plugs that are behind the passengers kick panel for corrosion?

Thanks I haven’t checked the white plug yet I am going to do away with the plug and solder them wires together but will che the plug on the compressor now

pete12345 said:

Cheers back home now for some checks can you tell me how you check the ohms on the compressor then because the original fault did say could be open circuit what ever that meens

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Open circuit means there's a break in the wire or the switch is open.

Yer cheers I am lost with electrics in the photo I’ve set the the metre with the engine off and touching the two feeds into the compressor i got a reading of 4- something then it disappears but good news I think when I switch car on no book symbol standing watching for the clutch to engage it does after a short while it did it twice then stops and when back in car there it is the dreaded book symbol switch off then start again and as if bye magic it’s gone again I’m still waiting for leak dye to arrive to test that but will check what the pressure says on the filler gauge to see I’ve it’s lost any any more tips much appreciated

Does anybody know where I can get one of these bad boys no part numbers on it

Mornin all and we begin again at least the sun is out right the clutch stays on when I bridge the relay now and the book symbol comes on after a short while when I put the relay in it doesn’t work just comes on for a second or two then turns off and won’t re engage any suggestions please

pete12345 said:

Does anybody know where I can get one of these bad boys no part numbers on it

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You've lost a leg ??

I take it you have tried a different relay?

J

No haven’t tried new 1 I’ve got to order a new one I’m waiting for it to arrive

tomcat59alan said:

You've lost a leg ??

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Want to borrow me crutches

In your photo of the meter the "1" symbol means open circuit so maybe you did not have the probes touching the pins inside the plug. If you saw 4 something that might have been the 4.2 ohms I had measured. In any case it sounds like your clutch is working. If the clutch relay is marked RL7 you can swap in one of the other RL7 relays for a test. The clutch will cycle on and off in a properly working system. If it does not do that you need to check how much gas you have in the system. I think it should be around 40 pounds on the low pressure side. If you really want to get this working it may be worthwhile to take the car to an AC specialist and get them to put in the correct amount of gas. At least then you would have that covered and can concentrate on the electrics.

Can’t take it anywhere at the moment it’s got no interior in it or dash I’m waiting for some gauges to arrive to check the pressure in the system what’s the low side the small pipe when I put my filler bottle on it the gauge on it says full in the green zone

With the engine running and bridging the relay does it actually blow cold, I mean really cold air?
If so then chances are gas is there. You could check the switch I mentioned earlier it’s down in the bowels and a PITA to get to but once you know where it’s easy to test.
As you say it clicks on then goes off and won’t come back, I wonder if for some reason it is switching to high/low pressure. So it’s worth finding it and checking with your meter if its shutting down the clutch/system.

You have Nanocom? Can you not do live data for AC system/control?

J

The trinary switch and low pressure cutoff (I think that is the second one) are much easier to get at and test if you remove the front bumper. Not all that difficult unless the two bolts holding it on are rusted tight. Don't break them off or you will not be able to attach the bumper. Consult Rave for details.

Thanks yer I’m sure it’s got gas in it I will check the switches I’ve I get time nxt weekend

Evening all progress report and it ain’t much but may shed a bit more light got home from working away all week battery completely flat something draining the power the only thing thing different than any other week was I forgot to remove the jumper wire on the clutch relay charged the battery removed the jumper wire no power to the clutch brand new relay still no joy and book symbol back up with engine still running put the jumper wire back in and the bloody compressor clutch fires straight up I’m not going to have time tomorrow but I will Monday check all the pressures in the pipes tomorrow the enemy wants to go to bloody garden show and had me laying concrete all day today so not a lot of time on the car today hopefully my symptoms may have affected someone else and they can remember the cure thanks in advance