Multiple Errors - Parking Brake, Suspension, Fun!

[Abram]

Hi again LR Family, I've got a new round of errors I'm trying to sort out, and I'm researching old posts here to see if I can find similar issues. Apologies if I'm creating duplicates.

2012 LR4 - 5.0 V8

To start with the most pressing: The parking brake. I use the parking brake every time I stop driving the vehicle, so it is exercised regularly but yesterday afternoon it suddenly started taking multiple presses of the lever to release (though it would consistently engage with one pull of the lever). Today it happens to be about 10º warmer than yesterday (about 90ºF) and when I was about to head out my truck never "settled" after starting and letting it idle as I always do (I wait until it has settled to about 5-600rpm), it never dropped below 1000rpm even after sitting for a couple minutes, and then when I went to release the parking brake it errored out and triggered a fault, U2002-92 (68) Switch general electrical failure - Component failure - performance or incorrect operation. I shut the engine off and turned it back on and idle went back to normal and the brake was disengaged. I'm concerned the EPB is about to crap out on me, but I'm trying to figure out if some signs I've seen have been warning me of this. After replacing my wheels and tires, I noticed that when I would activate the parking brake the truck would still have a bit of movement and never really felt like it was "secure". Additionally, since purchase, the truck will often squeal when braking in reverse, but never while driving forward. I also get a pulsing vibration in the truck when slowly releasing the brake from a full stop or when slowly coming to a full stop and I don't know exactly if it's related but I do see fault code U0421-68 (28) Invalid data received from ride level control module - Algorithm Based Failure from the ABS module. (See my previous thread for the details). Are these connected? The brakes were serviced a few months prior to my taking ownership last December.

Additionally my air suspension has been intermittently giving me a fault, particularly when trying to use access height, but every time if I just shut off the truck and turn it back on I can reset it and use all three heights again (I'm not running Johnson Rods or any sort of lift via my IID tool), it's triggering fault C1A13-64 (2E) Pressure does not decrease when venting gallery - algorithm based failure, and because I don't know the intricacies of these systems yet, it sounds to me like these are all somehow linked together.

Is there any possibility this is related to the battery? The voltages seem ok (12.6v when off and 14-14.5v when operating) but I have no idea how old the battery is. The reason I ask is that my driver and passenger doors are also intermittently triggering central door lock codes (though they've never not locked/unlocked as of yet) so I'm curious if maybe the battery is just wearing out and it's triggering other problems. I'm sorry for my lack of knowledge, trying to learn as I go and read up on as much as I can. I always appreciate any guidance offered. I do have a workshop manual that I've received via this group but I admit my mechanical knowledge is limited and I'm still very much a novice here.

 

[Abram]

Just want to update the thread. Interestingly the Parking Brake has resumed normal function and both engages/disengages with a single press of the lever, not sure why it went back to normal. It does still squeal when braking in reverse but I think that's another matter.

The Air Suspension however continuously will not enter access height. If I am in normal height, I can enter off-road height and go back to normal, but if I try to enter access height I get the Suspension Fault error every time. If I shut the engine off and start it back up I can clear the error and then it will enter access height and everything works normally. But if I drive, and then park again later and try to use access height it will still trigger the fault.

For now I'm going to leave it in normal height all the time while I figure this out. Ideally I won't need to replace the suspension (I'm not noticing any corners drooping or experiencing overnight drops or anything like that as far as I can tell.)

 

[Longtrail]

Take a look at this thread for the venting issue, I went down the rabbit hole with that one!

2012 LR4 Reluctant to lower from off-road suspension mode

Hi Folks, I just rebuilt the front suspension valve block (new o-rings) and now the LR4 seems to stay up over night (good news), the problem I have existed before doing this work and appears to be in the rear. Here's a summary of the issue. 1) I select off-road as the suspension mode and the...

www.landroverworld.org

These things are really sensitive to batteries; most batteries have a manufactured date on them so perhaps look at that (you may have to remove the battery). I just went through this drill and cleared some issues when I replaced my 2019 battery. I purchased a new battery from Costco ($175/ish) and it's been good ever since.

 

[Abram]

Take a look at this thread for the venting issue, I went down the rabbit hole with that one!

2012 LR4 Reluctant to lower from off-road suspension mode

Hi Folks, I just rebuilt the front suspension valve block (new o-rings) and now the LR4 seems to stay up over night (good news), the problem I have existed before doing this work and appears to be in the rear. Here's a summary of the issue. 1) I select off-road as the suspension mode and the...

www.landroverworld.org

These things are really sensitive to batteries; most batteries have a manufactured date on them so perhaps look at that (you may have to remove the battery). I just went through this drill and cleared some issues when I replaced my 2019 battery. I purchased a new battery from Costco ($175/ish) and it's been good ever since.

Thanks! Honestly that’s been my sneaking suspicion that the battery probably needs to be replaced and I bet it will resolve some things for me. Fortunately that’s easy enough to do in the driveway. Maybe I’ll start there and see where it leads.

Edit: I’ve determined my battery is nearly 5 years old and was swapped to an H8 size (Never really checked it directly before). It’s only a 760CCA which is probably fine but newer batteries seem to be higher/more efficient. I also noticed the battery hold down clamp is missing, how crucial is that?

 

[Longtrail]

Perhaps have the battery checked? Mine was 6 years so you're in the zone.

By "hold down clamp" do you mean the bracket and two threaded shafts that keep the battery in place? Not critical but I wouldn't be happy without this, I wouldn't want it bouncing around in my engine bay... Just my 2cents. Here's details/thread on the battery that I purchased:

P0232-24 (28) Fuel pump A - secondary circuit high - General signal failure - signal stays high

Hi Folks, following my recent Timing Chain endeavor, I'm getting the following code which returns immediately after it's been cleared: "P0232-24 (28) Fuel pump A - secondary circuit high - General signal failure - signal stays high" But unlike others, the truck runs absolutely fine, I've not...

www.landroverworld.org

 

[Abram]

Yes that’s the clamp I’m referring to. I ordered a replacement today, especially since I do (and have) off road this LR4.

I’m ordering a new battery and I’ll get that installed and go from there. Ideally that either sorts my problems or points me in the right direction.

 

[powershift]

It doesn't sound battery related to me and the ebrake may fail locked in-place if you keep using it depending on the problem. The CCA on my battery I thought was 820A. 760 might be a little low, but really you'll probably have less reserve capacity and that's where the killer is. The computers boot up and start sucking more juice when a door opens.