Hi everyone, I am going through a bit of an issue with a range rover I bought. When sitting stationary it is fine, no issues apart from the common P040D-00 code. As soon as I start driving and the car reaches the speed where the doors lock, all codes start coming up and she goes into limp mode.

Codes mainly are:
U0121-63 Lost communication with ABS control module
P279D-02 Four wheel drive range signal circuit

U121-00 Lost communication with ABS control module
U0128-00 Lost communication with parking brake module

B1C82-13 Headlamp washer relay coil circuit
U0121-00 Lost communication with ABS control module

B1D58-13 Television output circuit

P040D-00 Exhaust gas recirculation temperature sensor A - circuit high


I have looked at the TCCM and all prongs look clean with no evident corrosion, cleaned up the front main earth strap where it connects to the body under the front right wing and also replaced with a new battery fully charged and coded into the car, no change. Has anyone experienced similar after checking all that?

So tried a few more things looking at electrical connections for corrosion but nothing so far, I drove it a bit down the road and noticed that when all the fault lights come on the speedo stays at 0 even when moving.

IIRC the multiplug under the bonnet that goes to the ABS pump can let water in and corrode...

Worth a look...  Pete

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2014 L405 Autobiography SDV8 4.4 Loire Blue Ebony interior
2011 L322 Vogue SE 4.4 TDV8 Baltic Blue. Parchment over Navy Interior. Sold
2012 L322 Autobiography 5.0 Supercharged Ipanema Sand, Jet Interior. Sold
2002 L322 Vogue 4.4 V8 Epson Green, Ivory over Aspen Interior (Fatty Offroader) Sold
-Click for Project Fatty off roader-

Thanks, I checked that and no corrosion and all of the wires "seem" intact. Will keep hunting

You might try removing the headlight washer pump relay, being relay 1 in the auxilliary junction box, to rule out any possible impact of a faulty relay or headlight washer pump.

Can you disable drive-away locking in case the locking is causing an issue?

Well still no joy on this, have checked all fuses, looked at as many wiring joints as I can find, tried another ABD module but still get the same issues. Had it into an Indy specialist and they are stuck and cant find the issue. Truck keeps losing comms to the abs module but cant identify the issue at all?

Sounds like the speed sensor is working fine as apart from the exhaust gas temp they look like they are related.

It's not the speed sensor itself, that triggering, it's the processing that follows that being tripped, pretty much everything that should work isn't, that could be a dodgy frayed loom or water in a plug or loom.

Did this start happening after a storm, do you have damp carpets (wiring runs through the sills), or pooling water anywhere, rear wings, etc. because it's all bus based it could be anywhere on the bus ?

Andy Fuji White / Jet 2012 4.4 TDV8 Westminster