Anyone get HDC faults when offroading?

[toddjb122]

Got an HDC fault on the beach this weekend that was luckily fixed by a power cycle...

...was 5 miles from pavement, sand mode, truck raised, going about 35mph (right at that speed where the truck beeps at you, but doesn't lower) and all of a sudden "<beep> HDC SYSTEM FAULT...SPECIAL PROGRAMS CANCELLED...VEHICLE LOWERING..." and the next thing I now I'm in normal mode and my undercarriage is grabbing on to the occasional sand **** or driftwood stump that I usually don't give a second thought.

I stopped the truck. Turned it off. Waited. Restarted it and luckily it went away. I could have gotten off the beach okay but on a long offroad trip this could have been problematic. (It was also very fine soft dry sand so I sunk a little more than usual.)

In your opinion is this just an occasional gremlin to deal with or something to get checked out?
It happens to me very rarely...once last year it stayed on and required service.

 

[codemonkey]

Yup, I get that once a day on about 75% of my offroad outings. I posted about it a month or so ago, the general consensus was make sure the battery is OK, and check for software updates.

I haven't done either yet, actually, kind of wondering if I can see a pattern. I did talk to a former LR factory tech, now independent. He said with the canbus system, sometimes so much is going on in terms of signals from all the various sensors that sometimes the software doesn't quite keep up, and either misses or misinterprets signals. My two engineering degrees tell me it's probably a little more complicated than that, but it basically boils down to - occasional gremlin.

 

[toddjb122]

Thanks for the feedback. Unfortunate, but good to know I'm not the only one.

I'm an engineer as well, and if it is as described....sounds like a bug!

 

[drzjoint]

ya after i replaced the battery no more problems with hdc under warrantee free batt

 

[toddjb122]

Does 4WD LO Range work in this situation? (HDC System Fault)

If I did get stuck out there, that would have been a good option to get off the beach.

 

[JJABKW]

I had the same issue with my 05. After a two trips to the dealer and a new battery the service department replaced the height sensors. Problem solved. I can't seem to go off-road or tow with this beast without some sort of a warning light illuminating. I am running out of warranty!!

 

[roverman]

My 'fix' was a faulty ground wire. That's after the new battery and the new control module. Glad it was under warranty, that module was a couple grand.

 

[codemonkey]

Those are a couple of interesting ideas - height sensor, ground wire. Do you know which ground wire, it would be nice to be able to check out some simple things myself.

4lo does still work when this happens to me, though I haven't really pushed it. Turning the car off and on again makes the fault go away. In these conditions I'm usually more worried about ground clearance than traction.

 

[Houm_WA]

...yeah, but happening once a day at a 75% clip (on offroad trips) does not sound like occasional. It has happened to me once; and I'm fairly sure it's related to the battery. I know my battery is weak because I've run it all the way down 2 times. The first time I played my stereo without the car being cranked for at least an hour...that was a while ago. The second time, which was recently and after my HDC fault, I only played it for about 20 minutes and it "died" by itself.

If these issues are not simply the battery itself, then it's a voltage issue that is indirectly fixed by replacing the battery. I'm not sure about the canbus explanation....seems like if it had to do with the digital architecture then we'd get all kinds of non-sensical faults a lot more frequently than we do. On the contrary, there seems to be a specific connection between this particular fault (HDC) and a lack of electrical juice.

I plan on getting a new battery before winter.

 

[Houm_WA]

Oh...one more thing....we should be so lucky that this fault isn't more problematic. I was out in July wheelin' with a local club and one member had a newer L322 out wtih us. He got a bunch of faults and was stuck in Access height! Then....bad got worse and he lost Lo-range. Eventually, probably upon trying to "re-boot" the rig wouldn't even fire up.

...once he finally got it to crank, he had to turn around and go home.