What brand was the out-going compressor? If it was a Hitachi, did you change the relay and update the software?

 

It was AMK<>AMK

 

Hmmm....I see.

Well, maybe try an EAS calibration just for good measure. It's quick and easy (one beer) and can't hurt.

 

The compressor kicks the system into fault before I can even complete the LF side.

 

Hmmm....maybe try updating the software (via GAP tool) anyway.

 

Verified running AMK firmware.

I was really hoping to confirm or deny that (without any identifiable leaks in the system) its possible my front and/or rear valve blocks could be contributing to the symptoms.

 

There is no sensor for tank pressure, only gallery. You should be approaching 200psi unless the thing is on its stops and deflated, in which case it takes a couple cycles. You have a leak or an underperforming compressor. So the question is, when does this fault exactly occur? If it happens when the vehicle is lifting up then you have a leak or under performing compressor. If it happens after the vehicle has reached selected height, then you could still have a leak or under performing compressor but the leak could be the reservoir itself - which is someone common because they rust. The center block only regulates the reservoir. When lowering, the reservoir is closed to the gallery. When raising it opens to assist in quickly raising the truck - the center block open and reservoir pressure is dumped into the gallery AFTER the compressor has initially started. Then once the ride height selected is reached, the front and rear blocks will have closed and the center block will remain open and the compressor will continue to run until gallery pressure is reached - which infers the reservoir is filled back up. The center block will close off the server and the gallery will dump excess pressure.

 

Thanks for weighing in and, you're correct: I misstated about the tank pressure - I meant the gallery pressure indicated in the Live View of the GAP tool.

Here's the sequence:

• Start vehicle; compressor starts running.
• Gallery pressure gets to 110-130psi
• System faults on C1A20-64

I sure hope it's not my brand-new AMK compressor underperforming, so I suspect there's a leak somewhere.

I typically check for leaks using a spray bottle with soapy water; I did notice that it's more difficult to access the rear bags to check spray them - is there anywhere on the strut I should try to focus on?

Any other likely spots I should start with when checking for leaks?

 

Air tank might be difficult to check with the spray bottle as the holes in the cylinder may be on the side that is visually blocked by the frame. You should be able to hear it “hissing” though.

Not a difficult DIY job; even I have done it and I’m useless with a wrench!

 

WIth the compressor running, it is always hard to hear leaks. So as soon as it shuts off, you need to listen. Also keep in mind you can get creative.

You can test the system in some awkward ways. All the lines are 6mm and you can use push-connects and T-fittings with push-on bike valves (Schrader fittings) to creating a fill port. Then you can hook up a second smaller compressor to aid in inflation and see what happens. If you have a shop compressor with a tank, even better. Fill that tank, hook it up and now you can listen better by keeping the gallery pressurized. If you have a portable air tank, you can jump the compressor relay and run it into the tank to see what pressures you can reach and how quickly. Keep in mind, with the relay jumped there is no stopping the compressor. In theory they blow out at 250psi or so through the exhaust safety port - at least on the Hitachi.

I guess my point is to think outside the box with some basic fittings and a second source of air. Might just make diagnosing things easier.