P38A Springs back to air UPDATE

Capripaul said:

Thanks for al the reply's, I'm slowly working through all the advice starting with ensuring that all connections are clean and tight fitting (Rain is stopping play at the moment as well as having to go to work), Ill try and answer some of the questions below.
Yes new compressor which still works fine when it runs and thankfully no leaks at the minute.
I fitted a new pressure switch (seemed like a good idea at the time) this seems to test out fine switching as required with my meter across it.

Wammers ; I didn't know about the earth point I'll check this out, Thanks

The other thing I cant get my head round with the compressor is that I can make it run with the EAS unlock software, I'm assuming this still powers the same way through the relay etc. so at least some of the compressor circuit must be functioning or does it switch it a through a different route with the software.

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Saint.V8 said:

EAS Software will ask the EAS ECU to switch the relay to run the pump....just the same way as the ECU would command the relay to switch in normal operation....

If you can get the pump to run correctly by commanding it to via the software, I would say the ECU is at fault and is getting spurious electrical spikes from somewhere (driver pack as mentioned above) and it is modulating the compressor to run intermittently and in rapid succession.

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Wazzajnr said:

How did you test the pressure switch? In other words, did you use a known pressure to switch it on and off?

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wammers said:

Read my EAS post in the technical archive do the checks outlined therein. When run from diagnostics the thermal switch is bypassed. Diag just pulls the relay. If the thermal switch does not have continuity the ECU will not pull the relay.

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Capripaul said:

The diver pack is brand new and I also have tried a known second hand one from Kurt off this forum and with either fitted the fault stays the same. I've had an offer to loan an ECU but don't want to waste anyone's time and effort in posting etc. if its not the issue..

Pressure switch tested at work with known pressure supply and switches at 10 Bar/150psi

Sorry I've got that much info floating around my head about this at the moment I keep confusing myself, I've used your post on many occasions to try and make sure I know what I'm doing. I have tested the thermal switch a few time and have continuity, so I'm confident this is ok.

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wammers said:

It may have continuity through the plug but does it have a good ground. Check the ground point inside the wing.

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Grrrrrr said:

There's a plastic scouser nto far away. You could try swapping the compressor over with a know good one off one of the many cars on his drive. Just don't let him pick up anything heavier than a spanner and for God's sake don't get him excited so leave your missus at home, even if she looks like a strategically shaved bulldog in drag.

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tomcat59alan said:

I hope your not talking about Holiday chicken.

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Grrrrrr said:

Not heard much from @holidaychicken recently. I think he must be strapped to a bed somewhere with his scrotum painted orange and his arms in plaster.

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Grrrrrr said:

Not heard much from @holidaychicken recently. I think he must be strapped to a bed somewhere with his scrotum painted orange and his arms in plaster.

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