Not necessarily. If any of the brackets got bent, then the calibration could be fouled. In that case, there is no telling how the EAS tries to compensate. I would strongly suggest you purchase an IIDTool made by GAP Diagnostics. It will save you a lot of strife and money over the years.

 

That's great, thanks. First purchase was a GAP but it's in the workshop which isn't readily available. Great tool!

 

Quick update - technician has been over everything, sensors, brackets, wiring and still cannot work it out. Suspension is riding at height access and holding which is a start. I'm going to pick up and see what codes are throwing up on the GAP tool and go from there.

Frustrating, but hey, our friends at LR certainly like to make temperamental machines.

 

So what happens when you select Normal Height?

 

No adjustment function or special functions work.

Amber to red warning light on suspension. Beyond frustrated but not going to let it get to me. I'll run the GAP and share what comes back with findings as a few things changed from originally listed.

 

OK, so this is where I am at.

Radiator was replaced.
Drivers door wouldn't lock and this was repaired.
Replaced front rotors.
State inspection complete.

Suspension on front was sagging overnight but no error messages on start up.

Front struts were replaced but truck still dropped overnight so old struts were put back on.

The big warning message on the GAP IID getting it home is (and with the mechanic which left him confused):

"C1A13-63 (2E) Pressure does not decrease when venting gallery - Algorithm based failure - signal plausibility failure."

Definitely needs recalibrating as front sitting slightly higher than the rear.

On start up, car goes straight into off road mode, but then get amber and then red EAS warnings.

EAS compressor (hitachi I believe) and front and rear valve blocks were also replaced in the hope it was these.

Mechanic also tried a used EAS computer module. It removed the error but it was throwing back a VIN error which he could reprogram (pointed me to a dealer).

Truck sits at a ridable height and can occasionally feel it adjusting. So, whilst I can drive it, I'm being driven mad by the "brings" and cannot select any special features.

Tried GAP IID tool at home. Front adjusts but cannot seem to adjust and lower rear. At one point front left front jacked up! Now get another code:

C1131-92 (2E) Air Supply - Component failure - performance or incorrect operation.

 

Hmmm....I just don't think the Signal Plausibility Failure is the variety that would result in those symptoms, IIRC. You can look at the Calibration Live Values with your GAP tool and see if any are way out of whack. You can also re-calibrate it yourself, with that. The IIDTool user's manual has some instructions. It takes time, but it's not that difficult.

 

I'll try the calibration but not tonight.

Had a look at some of the live values:

Galley Pressure when engine off - 61.1psi. When running it works it's way up to around the 74.5-75psi range.

Current Height - FL -1in, FR -1in, RL 0in, RR -0in.

 

Dropping in the front is normally a valve block issue, of course can be struts. If one leaks the other will lower to as it takes up the weight.

Your gallery pressure is way low for operating state, see what is peaks at (compressor off). You should be well north of 149psi when it builds (I think mine hits about 190. Max system pressure is 250). Its normal for gallery pressure to drop though as soon as the compressor is off. A slow drop is normal, 1psi a second would be a fast leak and often means a defective exhaust valve.

Plausibility errors are the result of inferred faults, meaning something the system can not directly detect. If a height sensor was disconnect, you would hav a hard fault. If the sensor was giving an erroneous reading it *could* result in a plausibility error but should result in a hard fault because math and stuff.

Do you have lift rods (sorry if already asked)?

 

No lift rods. Truck is completely stock. Frustrating as I never had this issue when it went into the shop. Hard to not feel frustrated and broken by it. I don't have a garage so am limited with what I can do. I guess next step is either a dealership (argh) or find another indy specialist who might be able to resolve.