Hi guys... the fun continues in Milwakuee with my 2005 LR3 chasing electrical issues. Water found in drivers Floorwell and about 3/8" sitting water in Drivers wire channel along the floor.
Typical Sunroof drain issue at the elbow. I am fixing the drain issue. Drivers side was dry as can be and the "red splice" was fine and not corroded.

I don't see any splices in the wire looms in this channel until you get to the rear door area. So its not like the Passenger side with the "red wire splice issue" right where the water sits that I have read so much about.

What critical wire or system do you normally see shorting out when water sits in the driver's side wire channel on the floor? Symptoms include suspension failure message, transmission failure message (limited gears available),
check engine light, ABS light, Traction control light parking brake light, and HDC not available.

What have you found in that driver's wiring channel that has caused electrical issues?

:-)

 

* elbows, make sure you fix all four if needed. My rear ones were in good shape though, still replaced. I may have more good spare ends if you need em.

You should pull codes, but there is a chance its not water related but instead the brake switch. Care must be used when installing a new one, don't turn it too far. You can use a Ford switch, this is shipped and sold by Amazon, so legit.

 

Hi... Thanks for the reply. I changed the Brake Switch and Rear bulbs a few days ago. No difference. My battery is brand new (2 day ago) and Alternator puts out a good charge when running. So I'm not concerned on the charging piece.

Passenger side wiring floor channel was dry but I went ahead and redid the 2 into 1 red wire splice that everyone talks about.

I went over the under hood fuses and pulled each one... changed a few that were not 100% perfectly clean. I also pulled the TCCM... doesn't seem corroded or burnt up at the plugs... and it was bone dry....but I have a friend that has a spare with the same part # that is confirmed good..... so he is sending me to swap out just to confirm. I also ordered another Brake Switch just in case I messed up the one I installed.

As far as codes... I just bought a ICarsoft V2 reader for Land Rover and Jag. Amazon said it can read LR3. I first checked it on my Hummer and it read the codes. But when hooked to the LR3 and hit "diagnose" It cycles through like 27 checks trying to read the ECM data.. but fails on each of the 27 reads. Then at the end it says "could not communicate". So not sure what is going on there. I tried for like 5 mins then moved onto chasing wet wires in the floorwell. The space TCCM comes Thursday... so I will hook it up... put battery back in and give her a crank and see what I get... if issue persists... then I will try and ICarsoft again.

I may very well be back on here Friday asking for more help.

I don't have a history on the LR3 other than I bought it out of Arizona on a whim... has 75,000 miles. Is spotless on outside and inside and appears to never have been offroad. I literally have never see a cleaner LR3. Inside looks brand new. Cranks... pulls in and out the driveway... but dash light up like x mas tree... For the $3000 I'll chase the gremlins.

 

Yeah... gotta get codes. Also if you did not, check to make sure the brake lights are 100% proper type and installed/working properly. Its easy to mess those up. Also make sure it does not have a trailer harness installed, it could be bad wiring with it or installed wrong.

You may also simply have an ABS fault, as in one of the sensors is throwing things out of whack. Would explain why it kicked off only after you get moving a bit.

 

If you cannot get any code reader to communicate with it, it has a CANBUS issue. This low speed data network is a simple two wire data connection to several modules all over the vehicle. A short at ANY of these modules can cause total communication failure and give you the problems you describe. If water ingress has already happened, chasing down the damaged wires/module can be a big job, even for experienced automotive electronic specialists. One plus to the system design, unplugging a defective/damaged module will typically make the network able to communicate again, albeit without said module.
If I had to start somewhere, I would look at the air suspension control module, as it is located at the base of the left A pillar, and you described water in that exact area.
If you unplug that connector and see water, or worse, green corrosion, you are on the right path.
The attached pdf shows all 18 possible modules that share that CANBUS.

 

Hi Metaldog. Nice to meet you.

I finally got a reader to communicate. I was using an earlier version of ICarsoft LR2 tool. I found some online info that said the software on that one didn't support the
LR3. I was able to return it and get the updated ICarsoft Lr2 and now can fully access codes.

The main codes that I get are U0121 (Lost communication with ABS) and U0122 (Lost communication with Vehicle Dynamics Control Module). These 2 Errors pop up in multiple ECU (Engine, SRS, BCM, etc).

The water ingress was the driver front SunRoof Drain. The Elbow was completely gone and water was dumping right on top of the wiring in the left footwell area.

Thanks for the Air Suspension Control Module suggestion. I wasn't aware it was in that area. I've already replaced the TCCM... so I can rule that 1 out.... I'm going to starting working around the other modules starting with your suggestion on the Air Suspension Module.

Crazy that LR didn't design the system to identify which module went bad. Instead it just gives lost communication errors for other modules.. :-(

I'll let you know how it goes. Thanks again man.

 

Hi metaldog. I checked out the Air Suspension Module in the driver Footwell area. All connections are clean and look good. No signs of water.

The elbow that fell apart sits about 2 inches lower than the bottom of the Module connections. So I don't think water would have drained into the connections.

I disconnected the module (4 plugs) and tried to crank. But nothing would crank over. So something critical to starting must run through that module.

I did however find something odd that may be a clue. I reconnected the iCarsoft V2 and cleared all codes. The U0121 and U0122 wouldn't clear. The tool says
something like "error clear was successful but errors still present". When I do a manual diagnostic of each module it will connect and read codes with all but the ABS module. The tool says "read error" on the ABS module. This is odd. I hadn't seen this before. I tuened key off and disconnected the tool... then rconnected and turned key on. Same thing. Will not connect tot he ABS module.

Is this a clue pointing to the ABS module?