2012 LR4 Reluctant to lower from off-road suspension mode

[Longtrail]

Changing the dryer, if you have a Hitachi compressor, is straight forward. Hardest part will be disconnecting the hoses from the back side of the compressor (intake and exhaust hoses), and re-installing the compressor bracket when you reassemble due to a hard to reach bolt that need to be tightened. Once the compressor is out of the car, replacing the dryer is a Philips screw, twist and pull, install new in reverse order. If you have the compressor out, you can possibly inspect the exhaust solenoid and clear it of any dust. I'd recommend getting the new compressor hoses, there's a kit for the one that goes from the central valve block to the compressor dryer from Atlantic british, as well as some bits to replace the elbows where the old intake/exhaust hoses go if those got mangled during disassembly. Key to disassembly is to push the hoses into their push-to-connect fitting, and only then depress the release ring, before pulling the hose out.

You mentioned replacing o-rings on your front valve block - where did you source your kit, and did you find the o-rings to fit? I got a kit off amazon and the o-rings were close, but not the same, with several being quite a bit thinner in cross section. I didn't feel comfortable using them, so just cleaned the block out and have been having good luck so far.

The intake pipe goes up into the rear quarter area. The exhaust might also, but I'm not certain. You can see a picture of them in the parts diagram here: https://parts.landroverparamus.com/...0l-v8-gas/electrical--ride-control-components, #20 (intake), and #21 (exhaust, with the muffler can).

Thank you for the tips, I'll start investigating the project, I tend to watch lots of YouTube videos and then go from there!

I did change the front 'o rings and last night I did the rear ones, there's a great video on YouTube (starting with this one for general info - but on a RR Sport

) and then this one

there's also another one that was really helpful but I can't find that right now. I bought the 'o' rings from British Parts of Utah, here's a link:

Range Rover Sport LR3 LR4 Air Suspension Valve Block O Ring Seal

Range Rover Sport LR3 LR4 Air Suspension Valve Block O Ring Seal

www.britishpartsofutah.com

So far so good, the sizes seem really consistent.

 

[Longtrail]

Back to the rear valve... WOW, what a pain in the a&* to remove... Per a YouTube video I lifted the back of the LR4 and removed the spare wheel, this was supposed to give me access to the two pipes (left and right suspension) and allow there removal... Not so fast however on a LR4; there's a black and white plastic cannister in the way which I didn't want to move (not sure what it is?). The valve is situated on the drivers side (left hand drive) and can be seen once the rear wheel is removed. I first removed the electrical connection, then the lowest input pipe (the vertical one that goes in to the bottom of the valve), I actually removed the whole valve block so that I could manipulate it as needed. I then opted to remove the lower pipe which goes to the passenger side (this was black in my case); I moved the whole valve block to a vertical position and undid the fitting very very slowly (an open ended ratchet wrench would be incredibly useful if it existed...). The final fitting was somewhat easier because you can hold the fitting in place with a wrench and then carefully rotate the whole valve block around the fitting. I think it took about 50minutes to undo the three fittings. Re-assembly went way better than I was expecting; my biggest concern was not cross threading anything; I used a little silicon on the threads to try and help! I serviced the 'o' rings on the valve block...

Once re-assembled I played with different ride heights; it's definitely better and didn't throw any suspension faults (yet).

One question, I suspect that going from access level to off-road causes a lot of camber change in the tires and therefore lateral ****** on the tires (making it harder to move the vehicle up and down) which got me thinking should the vehicle be moving when you change ride height settings?

 

[djkaosone]

Back to the rear valve... WOW, what a pain in the a&* to remove... Per a YouTube video I lifted the back of the LR4 and removed the spare wheel, this was supposed to give me access to the two pipes (left and right suspension) and allow there removal... Not so fast however on a LR4; there's a black and white plastic cannister in the way which I didn't want to move (not sure what it is?). The valve is situated on the drivers side (left hand drive) and can be seen once the rear wheel is removed. I first removed the electrical connection, then the lowest input pipe (the vertical one that goes in to the bottom of the valve), I actually removed the whole valve block so that I could manipulate it as needed. I then opted to remove the lower pipe which goes to the passenger side (this was black in my case); I moved the whole valve block to a vertical position and undid the fitting very very slowly (an open ended ratchet wrench would be incredibly useful if it existed...). The final fitting was somewhat easier because you can hold the fitting in place with a wrench and then carefully rotate the whole valve block around the fitting. I think it took about 50minutes to undo the three fittings. Re-assembly went way better than I was expecting; my biggest concern was not cross threading anything; I used a little silicon on the threads to try and help! I serviced the 'o' rings on the valve block...

Once re-assembled I played with different ride heights; it's definitely better and didn't throw any suspension faults (yet).

One question, I suspect that going from access level to off-road causes a lot of camber change in the tires and therefore lateral ****** on the tires (making it harder to move the vehicle up and down) which got me thinking should the vehicle be moving when you change ride height settings?

Use a spray bottle with soapy water and spray everything to check if there's bubbles to truly tell if theres any leaks.

I typically raise/lower the vehicle while in motion. I don't like the amount of stress and unnecessary wear on the tires on pavement while stationary.

 

[Longtrail]

I'm not sure there are any leaks, it's definitely better on the front; the rear never appeared to have an issue and having serviced the 'o' rings it's effectively status quo.

I did get the suspension fault again over the weekend so the next part to service is the middle compressor valve. I tend to notice the fault occurs when the vehicle has been left on an incline (going up); the fault occurs when starting the vehicle although it also occurs at other times as well...

I took the compressor cover off today and note a new compressor may have been installed; it looks to be a generic replacement, curious if anyone knows what this is:

The sticker on the end of the compressor body says 328:

 

[Longtrail]

To answer my own question... I think this might be the unit (and not very good rankings) and others that mention the C1A13 error!

https://www.amazon.com/Suspension-Compressor-Relay-2010-2014-LR061663/dp/B07N43V4F6/ref=cm_cr_arp_d_product_top?ie=UTF8&th=1

Grrr :-(

 

[ryanjl]

If you want a genuine one, buy from the UK. LRDirect, Advanced Factors, etc.

Prices are considerably cheaper than the US and shipping is sometimes even faster than getting it from the US.

 

[Longtrail]

Thanks - I can do that. How do I know which one to buy, is it AMK originally in the vehicle or Hitachi? Once again coming from a place of learning! Do I have to re-program anything?

 

[ryanjl]

Hard to say. You could figure out what year yours is and use that. 2011 is the fuzzy cutoff. Prior to that, Hitachi. After, AMK. I will say that the the aluminum bracket underneath makes me think AMK.

Hard to know if it was reprogrammed to work with whatever compressor is in there. If it wasn't, replacing AMK with AML requires no reprogramming.

Another case where the iiD tool would be helpful as it would tell you what it was and allow you to reprogram if need be.

 

[ftillier]

IIDTool would tell you what is configured. My 2012 has a Hitachi.

 

[Longtrail]

It's a 2012 and looking on the Advanced Factors site they state this:

"Discovery AMK Suspension Compressor. Use LR078650 if you already have converted to AMK (or Standard from VIN BA589828) Otherwise you will need the full kit LR072537. You can also fit the Arnott P-2645 AMK Compressor if you still have the Hitachi style as it comes with a new bracket but this will not fit with the original plastic cover"

My VIN ends in CA631614 (there's states BA589828) so I'm wondering how the VIN numbering works, if mine is later then it implies AMK which with the aluminum plate I'm inclined to agree with you. Not sure yet what the AML is but so far I'm thinking LR078650 is the correct part number.

The IID Tool will come but right now it's not feasible, there are too many other factors (kids) at play!