Land rover LR3 Reservoir valve code air suspension disaster.. PLEASE HELP

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Broncoman95

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Hello everyone,

I have a land rover LR3 2006 V6 and have been dealing with a couple of strange issues with the air suspension. Ive researched all over for this issue, but Can only find 2 things about it and the forums just get cut off and end with no real help.

When starting the car, I instantly get a suspension fault when the compressor kicks on. I have scanned the codes, and I get c1a35 - Reservoir valve, and then shortly after, if I clear it and try and raise the car, I get C1A31 (front left corner valve). Upon these issues, I have put a new compressor, dryer, front valve block, and reservoir valve block in, and these codes and issues are still present. The weird thing about it all is that the front never really lifts, but the rear would lift and go into off-road height despite the fault. It wasn't until recently that the front lifted up a little bit.

I'm at a complete loss here... Ive checked a decent amount of things for leaks, but I'm starting to assume I'm dealing with an electrical gremlin. The rear would go up all the way in off-road height, but the front wouldn't move at all. Now, since putting in new parts, the back doesn't go as high when in off-road mode while the front stays around access height. Yet, at one point, I got the front to lift, which I Hadn't been able to do before. Even now, when it's at its normal height, the front is higher than before the new parts, but still not functioning properly. Ive read that "c1a35 - Reservoir valve" is typically an electrical fault, and when it fails, it causes other things not to function properly, which may be why I'm getting a front corner valve code. If anyone has any help, advice, or information, I would greatly appreciate it. I will take anything I can get.

In regards,
Jack
 

remember5

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You might try recalibrating the suspension. Attached are the files relating to the suspension which BTW is an extremely complicated system.
 

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Longtrail

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So:

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It's all pointing to a wiring issue, perhaps check the wires all look OK. I measured the resistance on my exhaust valve solenoid and got 15ohms. I have a spare reservoir block and could measure the resistance on that valve for you to compare.

Did you make any other progress with this issue? Do you have a gap tool or something to look at the valves? See long thread over here to see some images of valves opening:

 

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Broncoman95

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Hey, thanks a lot for your response.

Over time, after doing all that work, the issue stayed present but got a little better.

To start, the suspension fault still instantly goes on as soon as the pump kicks on. But what I will say is that now, for the first time ever, all 4 corners sit at a much better ride high. Never perfect or great, but a lot better than it was. And sometimes the terrain response controls work (WHICH NEVER DID BEFORE)

Now, when I put the vehicle in off-road height, it will raise, slowly of course, but it will go up. As soon as I drive in off-road height, I am instantly presented with a suspension fault warning, and the car goes back to normal ride height. This was an improvement from what it was prior as well. Originally, when I put the truck in off-road height, the front was lower than normal height, and the back would max out in off-road height like a South Carolina squatted truck.

I had made a post on another forum, and someone had told me to check the wiring near the frame horn on the left side slightly past the wheel. What some people say happens is that the wiring harness for the suspension rubs on the frame horn and can short out the wire or allow for corrosion. Of course, with my fantastic luck, the day I got that response, winter had woken up, and Ive had cold weather and snow since. Sadly, without a shop or any place to do work I've been holding off until some nice days. Im still gathering as much information as possible to prepare and find the issue when possible so I really appreciate your response.

Here is the response I got regarding the frame horn-

"Def sounds like electrical. Or you are using aftermarket parts which are often a crap-shoot on their own. I would look at the front left wheel well. When looking, go towards right side of the well towards the bottom. There is a large "frame horn" that is bolted or welded on. Being 2006, it should be bolted. Just three and they are not hard to get at. remove the bolts to get the horn out of the way and very carefully spend some some looking at all the wiring. It tends to rub on the horn and cause issues. By 2006 this should have been resolved with a new wheel well liner that sorta cradles the wires above the horn, but I have still seen it happen.

FYI, rear tends to go up because the truck usually raises the rear first before starting onto the front. This is in a matter of a half second or so though. I believe this is done to prevent a sudden and noticeable drop of the front if pressure is not just right in the system."


Not sure if it helps, but in the other forum I had wrote down the steps and process i went through changing parts to maybe help track down potential issues to pin point the problem, so here is that aswell -

"Hello DakotaTravler, Thanks for your response.

So as for this nightmare of an issue, here is the process I've been through:

My compressor ran and seemed fine, but I wanted to change the dryer to see if that was the problem; upon that, I opened a huge can of worms.

When I went to remove the main airlines into the compressor on the right side, they were just completely fused in, and the push rings would not move AT ALL. They were completely seized in there. Ive heard the common issue is that the compressor gets hot, and the lines melt into the fittings making it nearly impossible to remove. This, unfortunately, led me to have to cut the lines on the right side. Once I got the compressor out, I tried everything possible to get the rest of the line out, but the push rings were just destroyed. I think the fact that salt got in it and they fused together from the heat had just ruined it.

This was really annoying because it forced me to have to get a new compressor. I did actually order a cheap Compressor and bought a line rebuild kit that spiced a shark bite on from where I Cut the line. The kit worked... it gave me fittings, the line, and the shark bites. I got the new compressor and dryer in, tested for leaks, and turned the car on, and the same issue occurred. Got the reservoir valve code and then eventually the front corner valve code.

Next, I replaced the front valve block because I figured if it's not the compressor and I'm getting the front corner valve code, IT MUST BE THE FRONT VALVE, Right? especially because my front never lifts. For this part, I actually used an OEM land rover front valve block, cleaned the connectors, and tested it for leaks all went well. Got in the car... same codes, same issue.

Lastly, I bought a Cheap amazon Chinese middle valve block. taking off the Voss fittings, I saw tons of desiccant in the lines and said to myself, "this has to be the issue. Put it all in, tested for leaks, and had the same issues.

At this point, I stopped hunted all over for the codes and issues online but could barely find anything about it.

As you said, there was a point I thought maybe it's the cheap middle valve block I put it, but then I realized: All of these codes were present before changing the parts.. so how could it be the new part? SO CONFUSING
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And with the new parts, the front raised for the first time. There were times I could clear it, and it would stay off on the drive for a little bit, but then you open the door or something, and it would come back. It's always right when the compressor kicks on. I at least think all of the new parts are functioning. I am actually pretty sure there was nothing wrong with any of my stock parts, and I replaced them all for no reason. Although the desiccant in the dryer was certainly due, but that's about all.

Sorry for the overload of information, but I figured it might help try and find out the issue. I'm definitely going to have to check out that frame horn harness. I actually did read something about that, but the form was for the secondary code I get "C1a31 front left corner valve." but with these things, It could be corner valve issue causing for the reservoir issue even though I always get the reservoir valve one first. WHO KNOWS!

It's a very confusing, complicated issue and has to be electronic at this point, Right?

Thanks a lot for your advice; I will be sure to check it out. If you have any other ideas, please let me know!

In regards,

Jackson"


Sorry for the essay of a response. This has been a disaster of an issue, and worst of all it's not common. I haven't found anyone with a similar issue, and since there are 500 wires, it makes it so hard. I'll leave the link to the other forum if you would like to read it. The only real suggestion I got was to check the frame horn.

Thanks for your response, I'm all ears to any suggestions!

In regards,

Jackson

Link to the forum -https://landroverforums.com/forum/l...nsion-issue-land-rover-lr3-115006/#post847971
 

Tapps33

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Since it seems like this problem is "moving" through out the system, I would suspect something centrally connected to everything....more specifically, the air suspension module seems to me to be where your gremlins reside. As I believe the air suspension module for the LR3 is on the driver's side A pillar, if you've ever had any issues with the sunroof drains backing up, there's a better than average chance it's gotten wet. As someone who has dealt with a TON of LR3 & LR4 electrical gremlins from a sunroof "flooded" vehicles, it's definitely possible. First thing I'd check is all the grounding points on the driver's side. Make sure you're not just dealing with a bad/corroded/rusted ground. If that's not it, pull the EAS module and then open it up and see if there is any visual corrosion/damage. If it's not visually damaged, and doesn't smell like fried electronics, I agree with the advice above, check the wiring system for a short somewhere. You could also try a replacement module and see if the errors are still present. As it looks like they're not crazy expensive, it may be easier just to swap it and see what you get. Here's a used one I found on eBay for $135:

EAS Module

Other than that, I share your pain, I've been fighting my EAS for about 5 years now....trying to find the leak/faulty part.

Let us know what you find!!
 

Longtrail

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Are you confident that the RLM (ride leveling module) ECU firmware is correct for the compressor that you have installed (AMK vs Hitachi)? I've just been down that path and my issues went away once I had the right firmware.
 

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