Computer nightmare!
Well regarding the brake switch it's not like earlier RRC/D1/D2 set ups. The latest replacement on a P38/D2 is LR3 style and yes it must be installed specially.
On the older LR's you pushed down on the brake pedal, inserted the brake switch, and when you let go of the pedal it pushed in the switch and it adjusted itself. That is not how the newer P38/D2/LR3 Brake switches work. If you push the pedal down, insert it and twist it it will lock the pushrod of the brake switch out all the way and it can damage the switch or cause crazy brain farts with the LR3/RRS/RR.
To properly install it you leave the brake pedal alone, and when you insert and twist it into place a little blue tab rotates and locks the brake switch position setting it properly.
I was barking up the right tree with thinking my original brake switch was faulty. I just didn't install the new one properly. I tried to install it the right way after I found out I did it wrong, but it apparently damaged it. I had bought it from Auto Zone so I just took it back and got a replacement for free.
If that is not done in that order the switch is not properly adjusted and cruise control, HDC, and the transmission can go nuts from false readings.
My friend is a 20 year plus LR Tech and he's seen just about everything. His AutoLogic scanner was very detailed, but honestly it was showing so much garbage like seat position faults, and crazy stuff that yes you must be 100% familiar with it or you'd have no idea what you're really looking at. My LR3 had probably 50-60 codes pending for LR specific stuff from seats, HVAC, NAV, stereo, air suspension, and deep inside of all that mess was the PDI Short Circuit fault, and the brake switch fault. He said all that other stuff is standard and is not an actual fault it's just what the LR3 is communicating with and sending/receiving.
I also had replaced my D2 brake switch with the updated unit and I didn't do it properly. It worked, but you could tell the adjustment wasn't perfect. After removing it, and doing it properly it was good to go. Lesson Learned!
On the older LR's you pushed down on the brake pedal, inserted the brake switch, and when you let go of the pedal it pushed in the switch and it adjusted itself. That is not how the newer P38/D2/LR3 Brake switches work. If you push the pedal down, insert it and twist it it will lock the pushrod of the brake switch out all the way and it can damage the switch or cause crazy brain farts with the LR3/RRS/RR.
To properly install it you leave the brake pedal alone, and when you insert and twist it into place a little blue tab rotates and locks the brake switch position setting it properly.
I was barking up the right tree with thinking my original brake switch was faulty. I just didn't install the new one properly. I tried to install it the right way after I found out I did it wrong, but it apparently damaged it. I had bought it from Auto Zone so I just took it back and got a replacement for free.
If that is not done in that order the switch is not properly adjusted and cruise control, HDC, and the transmission can go nuts from false readings.
My friend is a 20 year plus LR Tech and he's seen just about everything. His AutoLogic scanner was very detailed, but honestly it was showing so much garbage like seat position faults, and crazy stuff that yes you must be 100% familiar with it or you'd have no idea what you're really looking at. My LR3 had probably 50-60 codes pending for LR specific stuff from seats, HVAC, NAV, stereo, air suspension, and deep inside of all that mess was the PDI Short Circuit fault, and the brake switch fault. He said all that other stuff is standard and is not an actual fault it's just what the LR3 is communicating with and sending/receiving.
I also had replaced my D2 brake switch with the updated unit and I didn't do it properly. It worked, but you could tell the adjustment wasn't perfect. After removing it, and doing it properly it was good to go. Lesson Learned!
The what not to do and what happens is most appreciated.
You are now the voice of experience.
The link below is something I did up awhile back after much learning re installing the switch. I see one of the files within has over 3800 hits now.
DISCO3.CO.UK Photo Gallery - Brake Light Switch Replacement
I did not damage my new switch prior to installation, but I could not get the new switch to test out when I put an ohm meter to each of the two sets of contacts. I eventually figured out that as shipped, the button was partially retracted and that the twisting motion when installing released the push button and then that allowed the contacts to function.
As to not moving the brake pedal to do the remove and install, I think I must have read that somewhere first and then figured out why it mattered later.
You LR Buddy is still a genius.
As to all those false codes, as I have a BlackBox Evolution, every few months I hook the Evo up to the OBD port and clear accumulated codes, false and otherwise.
I recall that to get many to stop being generated in the first place, I had to edit the CCF to alter the equipment list to more accurately portray the installed options/features in my 3.
I recall getting an error related to the Japanese pollution sensor not reading. The error code message was correct of course, as there was no Japan mandated pollution sensor installed. I hence edited the CCF to show "no sensor installed" and then that code ceased to return. There were many others.
You are now the voice of experience.
The link below is something I did up awhile back after much learning re installing the switch. I see one of the files within has over 3800 hits now.
DISCO3.CO.UK Photo Gallery - Brake Light Switch Replacement
I did not damage my new switch prior to installation, but I could not get the new switch to test out when I put an ohm meter to each of the two sets of contacts. I eventually figured out that as shipped, the button was partially retracted and that the twisting motion when installing released the push button and then that allowed the contacts to function.
As to not moving the brake pedal to do the remove and install, I think I must have read that somewhere first and then figured out why it mattered later.
You LR Buddy is still a genius.
As to all those false codes, as I have a BlackBox Evolution, every few months I hook the Evo up to the OBD port and clear accumulated codes, false and otherwise.
I recall that to get many to stop being generated in the first place, I had to edit the CCF to alter the equipment list to more accurately portray the installed options/features in my 3.
I recall getting an error related to the Japanese pollution sensor not reading. The error code message was correct of course, as there was no Japan mandated pollution sensor installed. I hence edited the CCF to show "no sensor installed" and then that code ceased to return. There were many others.
Last edited by bbyer; Oct 25, 2016 at 08:54 PM.
Yeah it's crazy what goes on in the LR3 and up LR's with all the technology they've got packed into them now. It makes my 98 D1, and both my D2's look stone age simple!
The juicy details of the improper brake switch install in the auto zone parking lot at nearly 9PM were honestly horrific! I just told my wife I'm gonna run to Auto Zone and get a new brake switch to fix the Cruise Control. Well I wasn't home almost 2HR later and my wife was freaking out.... After I had slapped in the new switch incorrectly as I know now. I pulled out of the parking lot, hit the first major red light and Bingo it went completely mental! I pulled over into a Starbucks parking lot and I made the mistake of rotating the Terrain response **** to wet grass I think. Well apparently in all it's brain farting state it somehow activated the HDC or it applied the brakes. All I know is I left the Starbucks, and tried to enter the Freeway and I couldn't go faster than 30-40MPH. I exited at the next exit maybe 1/2 mile down. When I slowed down a massive cloud of smoke was pouring out of my front fenders!!!! When I got out to look both front rotors were so hot they were actually almost clear as I could make out the vented slots from outside the rotors.. I let it cool down for a very long time, and with the LR3 not faulted it wouldn't barely move and it felt like the brakes were on. When it finally faulted and lowered the suspension it released the brakes and I slowly made my way home 15 miles. The brakes were trashed and good god did they squeal upon just barely touching them.
The next day I called my buddy he told me to inspect the TCM for corroded plugs (mine were actually good) with the exception of a very small amount of corrosion on the Yellow Plug. He said for me to probably get ready to pay 1K for LR to replace the TCM as it sounded like the issue. I said I'll get her up to you somehow!! So that's what I did. If I drove it without hitting traffic aka as not touching the brake pedal I was fine (another clue that had something to do with my issues). Once I got it to him we of coarse tried to get it to fault and it wouldn't so he just connected it to his AutoLogic setup and went from there.
I was very very lucky it wasn't the TCM. I just had a 22.00 brake switch, and the cost of gas money up to Austin, TX vs a 1K job at a local Dealership.
I sold my H3 Alpha for 16,100.00, bought the LR3 for 11,000.00. I had to buy a new alternator (starting acting up 4 days after owning it), I also noticed the front would drop to the ground overnight so I tore down the front valve block and removed some goo from the center valve and that fixed that issue. Then it had it's brain farts, and 22.00 later that seemed good. After a week of no faults I then slapped on some new rotors/pads (needed them before the Hot Lava event), some RR 19inch 7 Spoke take off's and new Michelins, then I grabbed an LR3/LR4 Expedition Roof Rack. After that I still made out like a bandit, and with the 2015-2016 NAV update she's good to go!
The people that owned it before me were taking it to the local dealership for service. They probably had it go nuts, along with the lowering front suspension, and the battery warning light and decided to cut their losses. I've honestly never sold a vehicle because of stuff like that. Normally if I sell something it's in 10 times better shape vs when I bought it.
I plan on getting myself a decent scan tool for the LR3 so I can work on it myself. My wife is now really happy with it, and with the resonator removed she loves the exhaust note. I was expecting to do some work on it as with any new to me used car, but the Hot Lava event and the brain farts were certainly new to me.
The juicy details of the improper brake switch install in the auto zone parking lot at nearly 9PM were honestly horrific! I just told my wife I'm gonna run to Auto Zone and get a new brake switch to fix the Cruise Control. Well I wasn't home almost 2HR later and my wife was freaking out.... After I had slapped in the new switch incorrectly as I know now. I pulled out of the parking lot, hit the first major red light and Bingo it went completely mental! I pulled over into a Starbucks parking lot and I made the mistake of rotating the Terrain response **** to wet grass I think. Well apparently in all it's brain farting state it somehow activated the HDC or it applied the brakes. All I know is I left the Starbucks, and tried to enter the Freeway and I couldn't go faster than 30-40MPH. I exited at the next exit maybe 1/2 mile down. When I slowed down a massive cloud of smoke was pouring out of my front fenders!!!! When I got out to look both front rotors were so hot they were actually almost clear as I could make out the vented slots from outside the rotors.. I let it cool down for a very long time, and with the LR3 not faulted it wouldn't barely move and it felt like the brakes were on. When it finally faulted and lowered the suspension it released the brakes and I slowly made my way home 15 miles. The brakes were trashed and good god did they squeal upon just barely touching them.
The next day I called my buddy he told me to inspect the TCM for corroded plugs (mine were actually good) with the exception of a very small amount of corrosion on the Yellow Plug. He said for me to probably get ready to pay 1K for LR to replace the TCM as it sounded like the issue. I said I'll get her up to you somehow!! So that's what I did. If I drove it without hitting traffic aka as not touching the brake pedal I was fine (another clue that had something to do with my issues). Once I got it to him we of coarse tried to get it to fault and it wouldn't so he just connected it to his AutoLogic setup and went from there.
I was very very lucky it wasn't the TCM. I just had a 22.00 brake switch, and the cost of gas money up to Austin, TX vs a 1K job at a local Dealership.
I sold my H3 Alpha for 16,100.00, bought the LR3 for 11,000.00. I had to buy a new alternator (starting acting up 4 days after owning it), I also noticed the front would drop to the ground overnight so I tore down the front valve block and removed some goo from the center valve and that fixed that issue. Then it had it's brain farts, and 22.00 later that seemed good. After a week of no faults I then slapped on some new rotors/pads (needed them before the Hot Lava event), some RR 19inch 7 Spoke take off's and new Michelins, then I grabbed an LR3/LR4 Expedition Roof Rack. After that I still made out like a bandit, and with the 2015-2016 NAV update she's good to go!
The people that owned it before me were taking it to the local dealership for service. They probably had it go nuts, along with the lowering front suspension, and the battery warning light and decided to cut their losses. I've honestly never sold a vehicle because of stuff like that. Normally if I sell something it's in 10 times better shape vs when I bought it.
I plan on getting myself a decent scan tool for the LR3 so I can work on it myself. My wife is now really happy with it, and with the resonator removed she loves the exhaust note. I was expecting to do some work on it as with any new to me used car, but the Hot Lava event and the brain farts were certainly new to me.
Last edited by Best4x4; Oct 25, 2016 at 10:56 PM.
The hot lava event is strange for sure. Usually when the brake switch goes ****, the LR3 won't let you select a special program. Maybe this was extra special since it was not a faulted switch but an improperly installed one. Glad you got it all sorted and that you have the patience and resolve to sort through issues like these, so you can enjoy the LR3 for what it is.
I noticed a reference in your previous post to cleaning goo out of the front block valve.
Usually that goo is dust from broken down beads in the Hitachi air dryer. As such, if your 3 still has the Hitachi air compressor installed, (and it probably does, as they are still a good unit), you might consider replacing the air dryer beads with fresh beads. The attached links provides some info.
DISCO3.CO.UK - View topic - Suspension Compressor / Suspension error
Compressor repair. - Australian Land Rover Owners
Usually that goo is dust from broken down beads in the Hitachi air dryer. As such, if your 3 still has the Hitachi air compressor installed, (and it probably does, as they are still a good unit), you might consider replacing the air dryer beads with fresh beads. The attached links provides some info.
DISCO3.CO.UK - View topic - Suspension Compressor / Suspension error
Compressor repair. - Australian Land Rover Owners
I noticed a reference in your previous post to cleaning goo out of the front block valve.
Usually that goo is dust from broken down beads in the Hitachi air dryer. As such, if your 3 still has the Hitachi air compressor installed, (and it probably does, as they are still a good unit), you might consider replacing the air dryer beads with fresh beads. The attached links provides some info.
DISCO3.CO.UK - View topic - Suspension Compressor / Suspension error
Compressor repair. - Australian Land Rover Owners
Usually that goo is dust from broken down beads in the Hitachi air dryer. As such, if your 3 still has the Hitachi air compressor installed, (and it probably does, as they are still a good unit), you might consider replacing the air dryer beads with fresh beads. The attached links provides some info.
DISCO3.CO.UK - View topic - Suspension Compressor / Suspension error
Compressor repair. - Australian Land Rover Owners
The reason it let me select the wet grass mode was because after a restart the faults were gone. Only when you were moving and using the brake pedal did the hot lava event errupt into flames literally lol.
Other than coating the interior of the rubber air spring, I have always wondered where the oil that eventually leaks out of the shock absorbers goes.
Does the oil turn into a sort of invisible mist and over time just exhaust out of the system or does the oil do its bit in plugging up orifices?
I must say, you have had an eventful few weeks with your 3. I take it as a good sign that your wife was concerned - that is always reassuring.
You seem to display the proper attitude regards your 3 - it is a challenge.
Does the oil turn into a sort of invisible mist and over time just exhaust out of the system or does the oil do its bit in plugging up orifices?
I must say, you have had an eventful few weeks with your 3. I take it as a good sign that your wife was concerned - that is always reassuring.

You seem to display the proper attitude regards your 3 - it is a challenge.
Other than coating the interior of the rubber air spring, I have always wondered where the oil that eventually leaks out of the shock absorbers goes.
Does the oil turn into a sort of invisible mist and over time just exhaust out of the system or does the oil do its bit in plugging up orifices?
I must say, you have had an eventful few weeks with your 3. I take it as a good sign that your wife was concerned - that is always reassuring.
You seem to display the proper attitude regards your 3 - it is a challenge.
Does the oil turn into a sort of invisible mist and over time just exhaust out of the system or does the oil do its bit in plugging up orifices?
I must say, you have had an eventful few weeks with your 3. I take it as a good sign that your wife was concerned - that is always reassuring.

You seem to display the proper attitude regards your 3 - it is a challenge.
So, I have got another thread going as this stupid thing now won't run... Except if I let it sit with the key in and set to POS 2 for about 10 minutes to let it pull up the transmission fault.
Basicly, with no transmission fault displayed, it won't start and ODB reports no codes.
When the transmission fault finally comes up on screen, it will start right up and run, albeit stuck in 3rd gear.
At that point though, there are a ton of COMM failure codes thrown and one TCM low voltage code.
My cousin thinks it needs a new ECM. What do you guys think?
How much trouble is it to swap the ECM out? I know it's pretty easy to get to, but from a software perspective?
I also ready that you cannot buy a used one from like eBay and throw in and reflash, is that correct?
Basicly, with no transmission fault displayed, it won't start and ODB reports no codes.
When the transmission fault finally comes up on screen, it will start right up and run, albeit stuck in 3rd gear.
At that point though, there are a ton of COMM failure codes thrown and one TCM low voltage code.
My cousin thinks it needs a new ECM. What do you guys think?
How much trouble is it to swap the ECM out? I know it's pretty easy to get to, but from a software perspective?
I also ready that you cannot buy a used one from like eBay and throw in and reflash, is that correct?
Check the fault codes for a common denominator. Are all the modules having trouble communicating with one specific module? That will point you to the culprit.
I just tried to install a used engine PCM and although it took the VIN number, it would not start. I had to buy a new one and code to the vehicle.
good luck
I just tried to install a used engine PCM and although it took the VIN number, it would not start. I had to buy a new one and code to the vehicle.
good luck


