Transmission fault, HDC, lowered suspension height -- resolved

Discussion in 'LR3' started by steve c, Dec 15, 2011.

  1. bbyer

    bbyer Full Access Member

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    I have a 2005 LR3 with 175,000 miles and all is working well. I might add that I spend about $6,000 a year in maintenance so I suppose that should not be a surprise. You did right in getting your 3 towed as replacing Jaguar engines in not quite the same as installing a junkyard 350 into a Chev.

    The attached link below is to my album within which are three sections related to the air suspension. I might suggest you spend a week or so reviewing and printing out the wiring drawings etc. Once you understand the air system, resolving the problem will just be a matter of time.

    In the meantime you might refer to the section regarding fuse F35P located in the fusebox behind the passenger side lower glovebox; also F26E, in the engine compartment fuse box. Removal of either of the fuses, (F26E is the easiest), will at least keep your 3 from dropping while you research the problem and the solution.

    Incidentally, in the tradition of "throw parts at the problem", the first thing to do is replace the brake switch. I say that as while it is probably not the fix for this problem or more likely, problems, you have to eliminate the obvious sources of problems prior to even attempting to fix the real concern.

    The other cheap first attempt is to purchase four factory tail light/brake light bulbs, (P21/5), from your LR dealer, (or from a Mercedes or Audi dealer), and replace all four bulbs behind the red rear lenses.

    Also it is rare that any display trouble code actually indicates the problem. The odds are you have a corroded wire in the air system front suspension cables. There are no codes for that so what you see for codes, (or not), is just an addled computer attempting to provide an answer for which there is no software code in its listing.

    If you have the 4x4 display page on your NAV, (which you allude to), that can provide a hint as to if a wheel sensor is getting information or not, or "bouncy" intermittent information as would be characteristic of defective wheel suspension wiring.

    One of the files in the album below contains the Land Rover Technical Service Bulletin where they allude to the suspension cable corrosion problem. I use the word "allude", as in the tradition of "never say you are sorry" or that a design is less than perfect, the TSBs tend to be a bit vague as to the problem; the solution is spend money and buy parts, in this case foot long replacement wiring harness section - of which I have a couple installed.

    http://www.disco3.co.uk/gallery/index.php?cat=15405
     
  2. Houm_WA

    Houm_WA Full Access Member

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    Holly....got any pics of your LR3 in this state? I have seen 4 of your posts on various sites and now question the validity of your posts. In case you are a troll, please post something to verify your problem. None of us have time for trolls.
     
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  3. hollygcape

    hollygcape Member

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    I am not a troll, just looking for answers and figured the more posts I made the better my chances of getting help were. I have had no one actually help me with anything this far and I'm begging for them at this point. Here are some photos for your viewing. I am including the state of the vehicle from the outside as well as the 4x4 menu.
    18643830_10158480760830478_296899277_n.jpg 18601643_10158480760185478_777442724_n.jpg 18600563_10158480759470478_660124218_n.jpg 18600709_10158480758440478_1887662937_n.jpg
     
    Last edited: May 20, 2017 at 4:52 PM
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  4. bbyer

    bbyer Full Access Member

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    I think I see good news - the fact your Nav appears to correctly display what is obvious from the jpgs of the 3 suggests to me that your problems are what I call "mechanical" rather than "electrical".

    By "electrical", I means wiring or computer type problems, in other words, stuff you cannot see or hear and hence hard to figure out.

    By "mechanical", I am suggesting more like a physical air leak however there can be electrical involved.

    I recall a similar problem on another 3 and it just turned out to be misconnected air lines near the air compressor. As such, I ask if just prior to the problem, was a new compressor installed, or were any of the air lines fiddled with near the air compressor?

    If so, then you will have to print out that block air drawing in the links I gave above and then follow all the lines near the air compressor looking for two similar lines that could have been misconnected.

    To do this you will be under the 3. That is a very dangerous place to be and unless you have spare fingers or hands available, support the frame on all four corners on jacks of some sort.

    Imagine what happens it all four air springs expell air at the same time, and they do! It drops in maybe two seconds - how do it know you ask? By the way, the Land Rover myth that leaving a door open inhibits dropping is false - that is what I term aspirational - and a dangerous one at best.

    As I think the air compressor piping is not likely the problem, then I presume that for a short period, that you can get the front end up even in height with the rear. I hope so, as if so, then shut the engine down etc, open the bonnet, and remove 20 amp fuse 26 in the engine compartment fuse box. Find it first before you start this procedure. (Sometimes it takes a pliers to pull the fuse so with all off, test remove F26E and then reinstall.) Removal of F26E then depowers the air system completely and of significance, shuts down the "after dark" auto level air release program.

    In the morning, assuming you got the 3 up the evening prior, hopefully the front end will be down again.

    If so, then this suggests an air leak somewhere most likely in the front end area.

    If overnight, there has been no lowering or very little, then the leak is what I would call "electrical" related - that is something is telling the compressor located air exhaust valve to open and also the front block valve to open and expel air from the system - well that or some variation of that.

    The odds are you have more than one problem in the air system, so finding and fixing only one of them will not totally resolve the problems. For example in the above, the three front block valve orifices could be mechanically frozen open so if the air compressor exhaust valve electrically opened as well, then the air in the two front air springs would be released. The rears would remain high.

    You could also have a small air leak in one of the front air springs and a defective front block valve as well; that would release air overnight to drop the front.

    While we can speculate all we want, the first thing is to get the 3 up long enough for you to remove the F26E fuse and then report what happens. With that information, the problem can be in time located - the fixing will be easy - the finding is the hard part.
     
  5. Houm_WA

    Houm_WA Full Access Member

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    ....okay, thanks for the pics. I still think it's an EAS Calibration issue.
     
  6. bbyer

    bbyer Full Access Member

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    EAS Calibration would be yes, easier, much easier.

    Pulling the fuse should help tell the story.
     
  7. hollygcape

    hollygcape Member

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    Having a hard time locating the air drawing you are speaking of when you said, "If so, then you will have to print out that block air drawing in the links I gave above and then follow all the lines near the air compressor looking for two similar lines that could have been misconnected." I pulled up the Suspension Compressor Replacement one posted on October 2012, is this it?

    Also, to answer your question about whether or not a compressor was recently installed, it was replaced 3 weeks ago. The guy made a comment stating he "ran out of time" and "hopes the land rover doesn't collapse anytime soon". We purchased it from a dealer who gave us a 2 year warranty on the suspension system (by our request). Our warranty was up 3 days after having the compressor changed.

    Since then we have replaced the water pump, front valve box (it's a week old), and rear back up light bulbs. We have checked the fuses and all seem to be in working order. We did a spray bottle test on the air lines for leaks with nothing to show. We jacked the car up in the front 2 days ago to see if we could get the front to fill with air with no luck, then disconnected the battery overnight to see if anything else changed. Nothing changed. When we reconnected the battery and started the vehicle, the suspension fault didn't immediately come on like it had been as long as the car was in off road mode. When in normal ride mode or access mode it comes on immediately. I haven't driven it to see if the red suspension fault comes on at 25 mph or not. My guess is that it will. Does this change what you think is wrong with it?
     
    Last edited: May 22, 2017 at 9:02 PM
  8. bbyer

    bbyer Full Access Member

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    This is the link to the air compressor piping layout along with all main parts named.

    It is a doc you can download and print out. Hopefully then you can follow the airlines going into the air compressor.

    http://www.disco3.co.uk/gallery/displayimage.php?album=3802&pos=1


    Regarding getting the 3 back up to normal height, I am not clear however on if you were eventually able to get your 3 back up to a near normal height before you disconnected the battery. If not, then disconnecting the battery overnight would not provide much information.

    Sometimes, upon engine start, for a short period until the computers have completed their POST routine, the air compressor will start up and send air to a low airspring. If one does enough engine starts and stops etc, then one can hopefully get the 3 back to at least normal height. Then either disconnecting the battery or pulling the F26E fuse will keep the system from deflating due to the computers instructing the air compressor located exhaust valve to open.

    Pulling the fuse will not stop deflation due to "mechanical" reasons, but that is the purpose of the exercise - to figure out if the problem is either mechanical or electrical. If it is a combination of the two, well that is not so much fun.

    As you installed a new front block valve, then it is probably OK and as you leak tested the connections they are also probably good. It is rare that the airline piping leaks but there can be leaks at the Voss connectors where the airlines connect to something. The Voss connectors are good, but like all connections, if not properly installed, they can leak. The link below is to a Voss connector cut thru.

    http://www.disco3.co.uk/gallery/displayimage.php?album=3802&pos=5

    This is the album where the air system diagrams plus Voss connectors etc are located.

    http://www.disco3.co.uk/gallery/thumbnails.php?album=3802
     
  9. Houm_WA

    Houm_WA Full Access Member

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    Holly, speed-related EAS deflations, to me, point out a calibration issue. Seeing your front and rear ends so disparate while there is no sign of an air leak, also points to a calibration issue. The story behind your mechanic's install of your compressor tells me that he likely skipped the calibration post-install altogether. Go get it calibrated!!!
     
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