I’m facing a new issue with my RRS. Randomly, either while driving or after restarting, the computer system disables the air suspension and throws the following error codes:

• C1A13‑64 – Pressure does not decrease when venting gallery (Orange Light)
  
• C1130‑66 – Air Spring Air Supply(Orange Light)
  
• U1A35‑64 – VIN Data (Red Light)
  

The VIN data issue is on me, since I replaced the suspension module with a used one after my original unit suffered water damage. Because of that, I get the red suspension warning light and the 30‑mph max chime every 30 seconds. I know I’ll have to buy a GAP G3 tool to fix that part. SDD will not program a used module (trust me, I’ve tried).

My suspicion with the other issues is that the compressor may be failing. The compressor sometimes sounds like a dying dog, although I can’t tell for sure whether this is a compressor problem or an air strut failure. When the failure occurs, the ride quality drops after a few minutes and the vehicle becomes bouncy. This is completely random—it can happen in the middle of a 30‑minute drive, or the car can go three hours without a single problem.

I’ve also noticed that during a power failure, the two front struts will lower but the rear stays up, giving the car a “stance” look—front lowered, rear higher. I haven’t seen any other signs that the air struts themselves are bad.

I’ve also noticed that when the VIN data error does not show up immediately (it takes 15–30 seconds before it appears), occasionally when it throws the other two codes, the orange suspension light will come on first before being overwritten by the red light caused by the VIN data error.

Would these errors be more consistent with a failing compressor or a failing strut? For what it’s worth, this Rover spent most of its life in an environment it was designed for—dirt roads and muddy conditions—so I wouldn’t be surprised if the compressor sucked in dirt over time and slowly killed itself. Back in 2017 it had all four struts replaced, and I believe it’s still running on its original compressor.

Edit: I forgot to mention that I notice that when I lower the suspension to access mode, it likes to go to extended mode or go into extended mode randomly. I don't know if it's related, but it should be mentioned.