Dear all, I’m looking for a bit of help with a haldex issue. I’ve looked through my search results and can find issues but they tend to point to the mechanical side of things.

I bought my 09 FL2 GS from an auction and on the drive one was quite pleased with it but noticed a diff whine… A common issue as read on many places so I booked it in for a rebuild at my local transmission specialist. They did the job and cured the whine but I now had the message “terrain response not available on my dash”. Took it back to them and explain that I’d not had the message before and they farmed it out to a local garage who cleared the code.
I have a Gap IID tool but I’ve not added the FL2 on to it yet but I can still read and clear codes so that’s a start. I got the following code in both the RDCM and the BCM:

U0138-00(2f) Lost communication with all terrain control module.

First thing was to check the fuse in the boot fuse box. This is fine. Checked the voltage and there’s power to the fuse.
Next job, check the plugs on the haldex. Now, the plugs were attached but the clips are not present so assume being brittle, we’re broken when removing them for the diff rebuild. Pushed them home and secured with a cable tie but the message and code remain.
I’ve checked power using a multimeter at the plug and there’s power but I haven’t checked the canbus for a voltage/signal at this plug (I’m not sure how to).

Is there a way to get to the wiring without dropping the rear subframe so I can check for damage? From what I can see, there seems to be some damage to the cable shroud so I’m guessing there may be more.

Managed to get a pic of the damage I can see.

also is there a way of checking the haldex ECU for signs of life?

All helpful pointers welcomed.

Makes me wonder if the "specialist" perhaps didn't unplug the Haldex, before attempting to remove the diff, which would likely result in cable damage.
To check the CAN, you can measure the resistance of the 2 CAN wires, which should be about 120 ohms. Hyundai Ioniq 5 Ultimate. The family car.
2009 Rimini Red SE TD4. Gone.
2006 Tonga Green i6 HSE. Gone.
Audi A5 convertible, my daily driver.
1972 Hillman Avenger GT, the project.

Thanks Nodge, a very reasonable assumption guessing they also snapped a stud clean out of the hub probably with excessive use of the dugga dugga gun… they had to own up to that.

So not a "specialist" then, unless they're specialist bodge artists.
Sounds like they've fubared something. Let's hope they've not screwed up the Haldex.  Hyundai Ioniq 5 Ultimate. The family car.
2009 Rimini Red SE TD4. Gone.
2006 Tonga Green i6 HSE. Gone.
Audi A5 convertible, my daily driver.
1972 Hillman Avenger GT, the project.

Talk to Bell Engineering, perhaps. FL2 XS SD4 Auto 2010 2012-2017 (21k - 91k miles) (MY2011)
FL2 Metropolis SD4 Auto 2014 2017- (16k - 77k+ miles) (MY2015)
Metro in its 11th Year of (Extended) LR Warranty / Full LR Service History
(Expensive, but Trouble/Worry free - hopefully?)

Nodge68 wrote:

So not a "specialist" then, unless they're specialist bodge artists.
Sounds like they've fubared something. Let's hope they've not screwed up the Haldex.

IanMetro wrote:

Talk to Bell Engineering, perhaps.

Joncorry wrote:

Nodge68 wrote:

So not a "specialist" then, unless they're specialist bodge artists.
Sounds like they've fubared something. Let's hope they've not screwed up the Haldex.

They were meant to be a transmission specialist, the diff doesn’t whine so at least that’s something. If I can measure canbus resistance and its 120 ohms as suggested, I’m guessing its the haldex ecu thats kaput.

Well I’ve resolved the issue. The haldex/rear differential control unit was sent away to a helpful chap in Crewe who checked it and verified that all was well and suggested another look at the wiring…. I looked and looked and got the same result. As a last resort, I googled all terrain control unit as this was the item the car was not communicating with. Turns out, its a posh name for the terrain response knob.
I prised up the control panel to find the green plug was not connected, plugged it back in an bingo - it works.

Lessons learned, check the terminology and check all the components, maybe start with the easy/obvious first.

And with that, it’s going up for sale as I’ve got too many land rovers having acquired a nice Defender 110.

The terrain response module is the computer that is in the plastic housing under the TR control knob.  Hyundai Ioniq 5 Ultimate. The family car.
2009 Rimini Red SE TD4. Gone.
2006 Tonga Green i6 HSE. Gone.
Audi A5 convertible, my daily driver.
1972 Hillman Avenger GT, the project.