2012 LR4 with front left locking caliper

[BobbyD]

OK I'm very mechanical, quite adept at auto mechanics, can do brake jobs 'blindfolded' BUT can't figure this out yet. 2012 LR4 just completed needed brake job including rotors, calipers, caliper brackets and well lubed slide pins, pads, and pad wear sensor (at front left caliper and rear). The front left caliper had been grabbing occasionally prior to brake job and caliper replacement. New caliper over-heated and seized/froze. I got a new 2nd caliper and have replaced it and both (left and right) full/complete brake lines all the way up in the front. Also complete fluid change and properly bled (all four) brakes 2x. Ready to roll, the Hill Descent Control (HDS) is showing fail indicator. This has been lighting occasionally, not very often, prior to brake job. Thoughts? What is making or keeping the front left caliper grabbing? Don't want to go after master cylinder yet. Thinking its electronic or HDC sensor that thinks its on a hill descent and grabbing the brakes. The 'internet' says bad battery, or inconsistent or battery fluctuation can light up HDC warnings. Thank you in advance, can't wait for the easy answer that's right in front of me

 

[jlglr4]

Did you scan for codes? I’ve also seen that bad batteries can cause these problems. HDC is controlled by the ABS system, so - possibly wheel speed sensor or reluctor ring problem. Brake pedal switch/brake lamp system also can trigger problems.

 

[jlach993]

Bro i had the same issue when my truck had 41k miles. CPO warranty first covered new calipers. Still didn’t fix it. It ended up being the master cylinder according to my receipts i just dug up. I didn’t question it, but i’ve always wondered why it only affected that caliper if the master cylinder was bad. I’m not a brake aficionado. It did fix the problem.

 

[jlach993]

Did you change caliper pins? Recheck and lube em up and replace it if you re-used them with the new caliper. It sounds like a caliper pin/master cylinder issue, either or.

 

[BobbyD]

Did you scan for codes? I’ve also seen that bad batteries can cause these problems. HDC is controlled by the ABS system, so - possibly wheel speed sensor or reluctor ring problem. Brake pedal switch/brake lamp system also can trigger problems.

Thank you, great points; will search further. Yes, I did scan for codes. ABS and right front (not the left front that is sticking) wheel speed sensor were lit up. I cleared codes. Prior to brake job I'd disconnected the battery so that it wouldn't light up ABS, wheel sensors, etc.. There were existing faults from when my 1st new caliper had been installed and froze causing entire truck to shudder and light up the dash with every idiot light in there...

Did you change caliper pins? Recheck and lube em up and replace it if you re-used them with the new caliper. It sounds like a caliper pin/master cylinder issue, either or.

Yes, new caliper brackets on both front calipers with new pins nice and lubed. Took both off again to double check, lubed extra, extra; sliding nice. Front left caliper opened up when I let pressure off with bleed. Still locks after closing caliper with brake peddle. ABS is cleared. The HDC still lights up. Will try new battery and let you all know.

 

[BobbyD]

Bro i had the same issue when my truck had 41k miles. CPO warranty first covered new calipers. Still didn’t fix it. It ended up being the master cylinder according to my receipts i just dug up. I didn’t question it, but i’ve always wondered why it only affected that caliper if the master cylinder was bad. I’m not a brake aficionado. It did fix the problem.

Wow! I'd also bled the master cylinder (specific) in addition to all 4 brake lines at each of the four caliper. Thanks for your receipts verification maybe that's it. Its crazy; makes no sense and as you [all] know all idiot lights are connected showing multiple faults with potentially one problem. Will try battery and then Master Cylinder (ouch) and let you know. Thank you!!

 

[BobbyD]

Did you scan for codes? I’ve also seen that bad batteries can cause these problems. HDC is controlled by the ABS system, so - possibly wheel speed sensor or reluctor ring problem. Brake pedal switch/brake lamp system also can trigger problems.

Hmmmm, Brake pedal switch? I had that fail in a late model Chevy Suburban. Will put that on the shopping list. Great point, it's short money too.

 

[jlglr4]

Thank you, great points; will search further. Yes, I did scan for codes. ABS and right front (not the left front that is sticking) wheel speed sensor were lit up.

I believe a bad ABS sensor can cause the brake to drag on the opposite wheel. Not sure why - maybe the poor signal makes the car think the other wheel is going too fast.

 

[BobbyD]

Did you scan for codes? I’ve also seen that bad batteries can cause these problems. HDC is controlled by the ABS system, so - possibly wheel speed sensor or reluctor ring problem. Brake pedal switch/brake lamp system also can trigger problems.

Yes, I have a nice scanner that is working overtime on this one. Replaced battery. Nothin', but never hurts to have a new one. I loosened master cyclinder to let pressure off. Didn't do it. Loosened front right (FR) ABS module line to vent. Nothing happened. Full bleed of all four brakes again. *Remember all new brakes lines, up front, both sides all the way up too. Never had any ABS faults (everything else though!!!). Reluctor rings are good. Some of this, probably the root cause, turned out to be wheel speed sensor(s). Likely the right side, as it was pretty dirty and had some rust on face of opaque sensor. Causing the left tire to 'slow down', overheat, seizing calipers. I cleaned both wheel speed sensors. New caliper works perfect. Still chasing lights; suspension, wheel angle, all-terrain mode, ride level. Replaced brake light switch. Getting there. Have been able to clear all codes, DTCs, all lights are off. Drives, climbs, and stops awesome. Now it slips out of (D) drive... Hopefully just potential past liquid spills and crumbs; on it now.

 

[jlglr4]

Could maybe be an adjustment needed in the shifting linkage. Spotted this thread suggesting shifting cable adjustment: https://www.landroverworld.org/threads/popping-out-of-drive.27788/

Maybe revive this old thread or start a new one on your shifter issue so it’s easier to find in the future. Any particular conditions cause it to pop out of drive?