Hi, I need to replace the rear differential control module, Part number (i believe) is HY32-4C117 AD
It was diagnosed being faulty after the 'E-Diff Not Working ' warning popped up!
I went on Topix spent my £20 for the hour and located and viewed the removal procedure. Topix shows the module on the right rear drivers side somewhere behind the panel behind the rear fuse box area.
Tried to find it today and the Module isn't there? managed to find the auto transmission module but no other! Could any one help? Thanks

Here you go

Click image to enlarge

Hi, thanks for the schematics, that is where I was hoping I should find it! but all I can see when I have stripped it down is as in these photos and according to the part number that is the auto trans module? Any further help would be much appreciated!




Last edited by Unclebuck on Mon Jan 25 2021 5:16pm. Edited 1 time in total

Try these the correct way round

Unclebuck wrote:

It's that one.

Changing the module requires a calibration to be performed so might not be a DIY job unless you have access to a suitable device.

Here's an excerpt from the workshop manual.
https://www.rrsport.co.uk/gallery/albums/u...20L494.pdf 2012 SDV6 - it's missing a couple of cylinders
2008 TDV8 - it was a labour of love and is much missed

Thanks for the help but the schematics you showed are the same ones I copied from the Topix web, the one you identified as being the rear diff control module, as a label on the other side (which is in the photos) I believe from the number relates to the Automatic gearbox module! Please advise thanks

The rear diff control module part number I have been advised it is is HY32-4C117-AD, the auto transmission module in the photo is EX53-4C118-AD unless I’m mistaken?

I wonder if there is a confusion of part names / numbers. The automatic transmission control module (TCM) is in the gearbox itself. The transfer box control module TCCM is in the centre console next to the Terrain Response switches. Maybe the box that you have is the rear diff controller but has been given a different name and hence part number somewhere along the way. 2012 SDV6 - it's missing a couple of cylinders
2008 TDV8 - it was a labour of love and is much missed

Can anyone confirm the correct part number for the rear diff control module? Thanks

RRSTDV8 wrote:

I wonder if there is a confusion of part names / numbers. The automatic transmission control module (TCM) is in the gearbox itself. The transfer box control module TCCM is in the centre console next to the Terrain Response switches. Maybe the box that you have is the rear diff controller but has been given a different name and hence part number somewhere along the way.

I belive its the right part why not disconnect it and see what errors come up to confirm its the diff unit

Update! Having taken my car before Xmas in to diagnose the issue with the ‘E-Diff warning’ etc, I was advised that the issue was with the Differential locking motor which sits on top of the rear diff and not the control module. So I purchased a new differential locking motor using the part number supplied by the garage ! They advised that it would need ‘coding’ so I got the part for them to fit. The locking motor I purchased using the part number supplied was the wrong motor ! The garage had removed mine and had to refit it back once they noticed the differences. The one I bought is more readily available than the one I needed and a third of the price! Typical ! Luckily I could return the bought item, but prior to buying the correct motor, I decided to swop the rear diff control module and see what would happen and guess what the dreaded ‘E-Diff warning message etc’ has cleared and I didn’t need to be recoding result!
The module is situated in the place you guys stated and was easy to swop.
Thanks for all your help.

Great result. Nice one 2022 P440e AB

Nice to get a good result.

Perhaps you need to change garages. Are you using an LR indie or a regular garage? 2012 SDV6 - it's missing a couple of cylinders
2008 TDV8 - it was a labour of love and is much missed

Hopefully my recent experience sorting a similar problem may be helpful to others:

I had the e-diff not available alert on the dash, which followed on not long after the diff seal was found to be leaking.

The early l494 to about 2015 (which mine is) have the diff pinion seal that is prone to leaking. The nut on mine was being particularly stubborn so ended up leaving the car sat around for a while. That lead to a fair bit of condensation build up particularly in the boot area, which I eventually found had got into one of the multi plug connectors into the e-diff control module. There were signs of corrosion around the connectors which looks like it shorted out and when I opened up the ECU it was burnt out.

In the process of diagnosis and repair I removed the whole rear diff unit. Taking the e-diff actuator off the diff means you can check the mechanism moves freely (I found a YouTube video of someone rebuilding a jaguar e-diff of the same design where you can see how it works). The motor rotated ok too, so I refitted it and eventually managed to get the nut off the pinion and replaced the seal.

That just left the ECU to replace. As far as I can tell there are 2 types of ECU, sometimes referred to as RDCM or Rear Differential Control Module. The earlier ones are in a metal case as pictured in this thread. The numbers on the casing for mine was EX53-4C118-AE. I couldn’t find at replacement anywhere and eventually found the part had been superseded. The revised part number is LR083860. Unfortunately that isn’t on the part itself though and it corresponds to HX53-4C118-AA. The other type of ECU has a black plastic housing and different connectors, and as far as I can tell are on later models, maybe 2016 on. They are fairly easy to find second hand unlike the earlier metal case ones as per the part numbers above.

I ordered the new ECU from Land Rover to find this out. It’s about £500… Land Rover also said it would need coding which turned out to be the case, although only because it had a newer software version on it. Initially just plugging it in gave the same e-diff fault on the dash. It also had additional fault codes in the transfer case and chassis control modules saying they were missing a message.

GAP were super helpful when I contacted them and after flashing the RDCM it was all sorted. 2015 Range Rover Sport Autobiography 4.4 diesel
2011 Discovery 4 HSE 3.0 diesel