Glad I could help, I guess. Kept you from diaging can bus and vehicle dynamic control modules, eh?

 

Greetings, all. I have a similar situation: 2007 LR3 HSE had sunroof drain leak into the passenger floor. Days later started HDC & Transmission fault warnings, F on dash, System Fault Special Programs Not Available, Special Programs Off, Suspension Lowered, Limited Gears Available.

Using IIDTOOL these faults have been cleared numerous times and recur:

Engine Petrol

• P0118-00 (E8) Engine coolant temperature circuit high input

Transmission

• U2023-86 (AF) Control module network signal calibration data - Bus signal/message failure - signal is invalid

Vehicle Dynamic

• U0401-68 (2B) Invalid data received from engine control module/powertrain control module - Algorithm based failure - event information

The vehicle sometimes starts OK, other times barely turns over, almost stalls, I give it a little gas, continues running. Limited gears available.
I have driven vehicle around the block several times around 30MPH. Suspension is stuck in low and with limited gears available. I read lots of threads and checked/did things that worked for others:

-cleared out blocked sunroof drains; loosened carpets and door sill trim; dried interior completely with small heater. All dry now.

-replaced brake switch and bulbs with factory parts/bulbs

-replaced battery

-steering angle sensor reset (turn wheel to lock, hold for 3 seconds, turn to opposite lock and hold for 3 seconds then back to center)

-hard reset, codes come right back

-pulled and cleaned TCCM, no obvious damage on module or connector

-checked fuses

-replaced engine coolant temperature sensor, cleared P0118-00 (E8) Engine coolant temperature circuit high input fault, fault recurs

-while engine running, GAP IIDTOOL reads 14.1 Volts- does this confirm alternator is working correctly?


Vehicle has been off road for more than ten days and I'm running out of steam. This week I have an appointment to bring the vehicle my local independent service shop who has serviced the vehicle before. It's about 20 mile trip to the service shop. The main road is 50MPH, back road route is 40MPH. I don't know how fast the vehicle will drive in this condition. Is it safe to drive 20 miles as is or does it need to be towed to service?

Thanks for your feedback.

 

Your problem is likely in the coolant temp sensor wiring. Start by following the wiring from the sensor, under the plastic engine cover, and between the intake manifold and passenger cylinder head to look for damage or breaks. check for continuity between the sensor and the ECU.

 

@steeveo67, thanks for the suggestion. It is my first time under the hood and I don’t yet know my way around the engine compartment. On the underside of the plastic engine cover, I did notice evidence of mouse chewing but have not yet noticed any mouse nest or mouse poop around the engine.

1.) If I disconnect the negative battery cable, is it OK to put an electrician’s tone on the coolant temp sensor wire to help locate/trace it back to the ECU?
2.) In the ECU pinout diagram above, is the wire I’m tracing/testing the T128 identified in yellow at the ECU?
3.) (I’ve searched online but can’t find it…) Can someone point out in the attached photo exactly where the Engine Control Unit ECU is located?

Finally: if I get no further, can I safely drive the car in limp mode at 40MPH twenty miles to the service shop or do I need to have the vehicle towed?

Really appreciate the help, thanks!

 

1. Yes. I'd disconnect the harness from the ECU to be safe though
2. No. That is the oil temp sensor. I don't know which one is for the coolant temp sensor.
3. Back left corner of the pic, behind the battery. There are 2 control units. Smaller silver one is the Transfer Case module. The bigger one with 2 big connectors is the ECU.

You probably *can* but I wouldn't drive it. The wires on the left side of the photo above the valve cover are the temp sensor wires. If there were signs of rodents, I'd visuall check those wires first. You may not even have to check continuity at the ECU if you find an obviously broken wire there above the valve cover.

 

@steevo67, as though you had seen or imagined exactly what happened, you are ABSOLUTELY CORRECT regarding both the cause and the solution. I removed the plastic engine cover again, found wires coming from the sensor I had just replaced, and was surprised to find two wires had been eaten through. I had room to solder in two short sections of replacement wire. I turned the ignition on, problems gone. I used GAP IIDTOOL to clear faults, restarted and all clear. No dash warning lights, no brake light, no check engine light, all the special programs are available again. After two weeks dead in the driveway, went for a 45 minute drive, truck is running perfectly, zero faults.


My "flood" of errors became evident about a week after a water intrusion from blocked sunroof drain and I suspected corrosion but the cause was mice eating wiring. Perhaps not unrelated, in wet rain, mice were looking for a nice warm dry spot to make a nest. Now I'll need to figure out how to discourage the mice from returning. As I said, this my first venture "under the hood, " I learned a lot and am gratified and relieved to have resolved this showstopper. Thank you @steevo67, and thank you to all contributors and forum admins for supporting this lively community, and Atlantic British for parts and guidance. Cheers, All.



Mice ate through wires connecting the engine temperature sensor to the ECU. (Courtesy: thanks to @steevo67 for deducing the cause.)

Broken wire section(s) were replaced.

 

Glad I could help, much like the folks above in this thread helped me! When I lived in Germany, they had a device that hooked to the battery and repelled rodents. It was a big problem in the rural areas there. I'm sure they sell something similar here on Amazon no doubt.

 

d'CON used to make rat/mouse poison in these small cardboard containers that would work well anywhere flat and away from high heat in the engine bay. Used to be a somewhat common issue we saw at the BMW shop I used to work at that was near a more rural area. We would fix the wires and put a box somewhere under the hood and the customer would usually be fine after that.

 

Hello team - Im resurrecting this post as I have been trying to solve for an issue on an L322 - So PLEASE dont scold me for mis-posting in the wrong area. Im not getting a ton of feedback in the various Range Rover L322 areas so I figured I would try here since they are similar trucks, same engine and the OP here has similar issues as what Im seeing. Does anyone mind lending a hand as Im desperate to find an answer on my own. Thanks in advance for reading this really long post!

2008 Range Rover full size, L322
4.4 Jag engine
80k miles

Same issues as the OP but mine seems to be centered around the ECT Coolant Temp Sensor. Its a very hard start and only if I floor the gas pedal, or feather it, will it run. It starts and revs up a bit and then almost completely stalls out and then maybe will idle high - about 1200 RPM. Coolant fan is on high and the idle never really comes down, nor does the fan turn off or down. All kinds of TCCM faults (see below) and in limp mode. I also suspect that because the ETC is reading -40 and never really warms up past about 30 degrees F (its 80 degrees F currently outside), that this is causing the rest of the faults. The dash gauge for the Temp never budges until 15-20 minutes of idling where it suddenly will jump immediately to the middle. (As a side note I drove to a carwash a mile away for a test drive. When I drove it through, as water sprayed from underneath, the temp gauge danced a bit, down to zero and then back to middle - did this 3-4 times and then not again. Another note, I tried to fold the mirrors in by pressing the button near the window controls and it triggered another transmission fault code on the dash!!!)

Heres what I've done:
New ECT (OEM) Sensor
New Battery
New Alternator
New Lower Rad hose with thermostat
New upper thermostat
New OEM Brake Light bulbs

I scoured the engine for any broken wires. I confirmed Im getting 5v from the ECU to the connection that runs across the upper intake. Im also seeing on cold, about 44ohms on the new ECT and "IF" I can get it running, I also found the wires from the ECU and tested there as well, getting 5v. Lastly, I ran from the dongle of the ECT to the ECU wires as close to the harness as I could, a bypass set of wires and the same result. Its like the ECT is completely unplugged!!

GAP Scan:
L322 - Range Rover 2008
Vehicle scanned on 01-06-2024 12:28
Using IIDTool Pro V4.0 B5258
ATCM-Terrain Response

• U0401-94 (2E) Invalid data received from engine control module/powertrain control module - Component failure - unexpected operation
  ( on 29-05-2024 12:07:38 at 145752 km )
• U0402-94 (2F) Invalid data received from transmission control module - Component failure - unexpected operation
  ( on 29-05-2024 12:07:36 at 145752 km )
• U0416-94 (2F) Invalid data received from vehicle dynamics control module - Component failure - unexpected operation
  ( on 29-05-2024 12:07:36 at 145752 km )
• U0403-94 (2E) Invalid data received from transfer case control module - Component failure - unexpected operation
  ( on 29-05-2024 12:07:38 at 145752 km )
• U0421-94 (2E) Invalid data received from ride level control module - Component failure - unexpected operation
  ( on 29-05-2024 12:07:36 at 145752 km )

IPC-Instrument Pack

• U0248-87 (2F) Lost communication with remote driver utility module - Bus signal/message failure - missing a message
  ( on 29-05-2024 12:07:41 at 145752 km )
• U0401-68 (2E) Invalid data received from engine control module/powertrain control module - Algorithm based failure - event information
  ( on 29-05-2024 12:07:49 at 145752 km )

PAM-Parking Aid

• 0x0001 Unknown

PCM-Engine Petrol

• P0118-00 (AA) Engine coolant temperature circuit high input
• P0116-23 (AA) Engine coolant temperature - circuit range/performance - General signal failure - signal stays low
• P0480-14 (28) Fan 1 control circuit - General electrical failure - circuit short to ground or open (IGNORE THIS --I UNPLUGGED THE FAN ON PURPOSE TO SEE IF ANYTHING CHANGED)

TCM-Transmission

• U2023-86 (AE) Control module network signal calibration data - Bus signal/message failure - signal is invalid
  ( on 29-05-2024 12:07:45 at 145752 km )

VDM-Vehicle Dynamic

• U0401-68 (2B) Invalid data received from engine control module/powertrain control module - Algorithm based failure - event information
  ( on 30-05-2024 14:03:37 at 145752 km )

VIM-Immobilizer

• B1101-73 (28) Comfort relay - Mechanical failure - actuator is stuck closed
  ( on 29-05-2024 12:08:36 at 145752 km )
• B1B01-87 (2E) Key transponder - Bus signal/message failure - missing a message
  ( on 29-05-2024 13:34:42 at 145752 km )