After 3+ years the AHC is striking again. On a short 15 min trip this morning I felt the rear end suddenly very stiff right away out of the driveway jarring the vehicle over small bumps, about 2 miles later the AHC off light started flashing. Upon arrival to my destination I found the rear end sitting on the bump stops. I inspected the system and saw no visible leaks at the globes, lines, or hydraulic shocks. Fluid level high in the reservoir. On the ride home the light continued to flash but the ride did improve. At home I found the car sitting at roughly the appropriate height. Quick research pointed to the rear height sensor so I took that off to clean and inspect but found the contacts inside to be very clean with minimal dirt inside. I put that back together and reinstalled to find no change. So next I pulled out techstream and I have a c1713 Rear Height Control RH Circuit Malfunction" and c1718 "Pressure Sensor Circuit" code. I'm leaning to the rear sensor but I should probably learn how to test the sensor batteries to confirm right? Additionally I could crack open and test the front two sensors too? I'm seeing online that despite the rear sag and rear height control code it does not necessarily mean the fault is there?
Background on the rig I have had it for a little over 3 years and a little under 30k miles. I baselined the AHC when I got it with new fluid and had a ton of issues when I got air into the system bleeding. Fortunately bleeding like 50x sorted that out after many hours of diagnostics. I checked the pressures just 2 or 3 months ago and was surprised to find the rear and front pressures still holding well. I also measured ride height on the front and both sides were to spec. Until today ride quality has been excellent.
Techstream data photo is sitting on a relatively level place with rear on bumpstops. Strangely after moving the vehicle from this spot to the driveway the rear end came up to it's normal height.
Please advise.
Background on the rig I have had it for a little over 3 years and a little under 30k miles. I baselined the AHC when I got it with new fluid and had a ton of issues when I got air into the system bleeding. Fortunately bleeding like 50x sorted that out after many hours of diagnostics. I checked the pressures just 2 or 3 months ago and was surprised to find the rear and front pressures still holding well. I also measured ride height on the front and both sides were to spec. Until today ride quality has been excellent.
Techstream data photo is sitting on a relatively level place with rear on bumpstops. Strangely after moving the vehicle from this spot to the driveway the rear end came up to it's normal height.
Please advise.