I want to start off by thanking everyone here for a great site. I lurked around for a while before I bought my Lr3 in June of '14. Ended up buying a Tonga Green SE V8 with Nav. that had 86k miles... all service records and computer updates along with almost all known failure parts replaced.
If you don.t want to read this long story scroll to the bottom.

Anyhow... So one morning about 2 weeks ago I went to hop in the Lr3 and at first it wouldn't start... then after cranking for awhile all the warning lights and failures start popping up and the truck drops to the floor. Trans, HDC, special programs off etc. etc. crap...

So I download the 4dcan software hoping to pinpoint the problem... previous experience with PA soft for my E36 m3 has proven essential to diagnosing the problems with that beast so I figured this would be my savior. While I like the fact that it (4dcan) will communicate with all the body systems, I was not able to decipher all the "lost communication" and other errors that I was seeing. and one error that puzzled me a bit that wasn't mentioned anywhere else... coolant temp too high??? more on this later.

So what do I do? everything that everyone else does with we get Christmas lights in an Lr3
-Stop light bulbs( had phillips bulbs in there) I thought awesome this will solve it with LR oem bulbs! wrong... no change.
- Brake switch... gotta be it... wrong...
- ok ok... the battery... my battery was an interstate battery that looked good, tested good, but the + post was canted just enough to make me suspicious... so I replaced it with no change. darn.

On to the wiring.... had to be corrosion... while the battery was out I dug behind and found the transfer case module with corrosion in the plugs and pins... thought for sure this was it... nope.
So... I break out the windows tablet loaded with the 4dcan software ( pretty cool btw if anyone is looking for a portable diagnostic tool) and see if anything changes... but its all the same errors.

I take a break and try not to curse at every LR I see driving down the road... which luck has it.... there were an unusual amount that day....
While I was checking the oil on the M3 I noticed RAT droppings on my motor!!!! freaking out Im going through it with a fine tooth comb... and then realize that My LR was parked where my M3 was...

Now I zero in on the Coolant temp too high code because that would be caused by a broke wire... annnnnnd there it is... under the plastic engine cover a beautiful Rat nest and a chewed wire!!!!
So moral of the story... the broke coolant temp wire caused all these problems.... patched the wire and all problems gone!!!

as for the 4dcan software and tablet combo I have going on... I bought a Winbook tw801 from microcenter loaded with windows 8.1. according to RSW solutions, the software will not work with windows RT version but this tablet had the full windows 8 OS so it works with out a hitch. of course you will also need the wifi elm327 adapter to go with it... but at $139 for the tablet and $30 for the wifi adapter... Id call that a cheap portable tool to carry in the vehicle at all times. Support from RSW was awesome as I was emailing him while purchasing the tablet for assurance that it would work with his software.
thanks everyone again... disaster averted
Scott

 

Nice!

 

I read a couple of years back about the same thing - rats had discovered the coolant sensor wiring on top of the engine but under the plastic cover, had lunch, and the owner was walking.

I presume the two conductors were shorting together as I would think that disconnecting the sensor should just put the system into a default condition at 80C and or the oil temperature sensor output would take over. - that is how it is supposed to work anyway.

At any rate, well done with your computer sleuthing but I think it was your Mark 1 eyeballs that really first discovered the hint of the problem and the computer stuff was the backup to what you already suspected.

One of the problems with all this computer analysis stuff is there are no codes for broken or corroded wires; it still takes the human mind and skills set.

 

Glad you found the chewed wires, rats can be a real pita. I am still tracking down rat issues on our RRS, currently a 6000 pound paperweight........how is the rsw solutions 4dscan software compared to the other diagnostic tools out there? The price seems very competitive. thanks Phil