This happened a couple of times on my trip to France and about 7 or 8 times on Saturday when travelling to Ireland, so is starting to annoy me...

Driving along at a steady speed - ie maintaining a certain speed - say 45mph or 60mph, with foot just lightly on the accelerator to just move enough to allow for any variance due to road conditions and normally when in a line of traffic when

Ping! Faults start coming up on the dashboard - Engine - Transmission - Height, whereupon the car will not accelerate and starts to slow down, the chasis lowers into access mode and is just basically non-responsive. Bit scary as you have to safely get the car to the side of the road and stop. Switch the engine off & on, then all is back to normal, away you go again!

Accelerating, slowing down, normal driving and its all fine. Feathering the throttle and its disco light time...

Fortunately I have an IID tool, so the codes are below but I think its the P117D-00 (6 message that is the most informative.

A google of that brings up an issue on disco3.co.uk about brake light bulbs and brake switch, which doesn't really seem as if it might be related to this issue, so anyone got any ideas or experience & how to rectify? (I will of course try those if nothing else)

Quote:

Engine TDV6

P117D-00 (68 ) Fuel volume regulator control exceeded maximum control limit

Instrument Pack

U0132-87 (2E) Lost communication with ride level control module - Bus signal/message failure - missing a message
U0159-87 (2F) Lost communication with parking assist control module - Bus signal/message failure - missing a message

Parking Brake

U0100-87 (A8 ) Lost communication with engine control module/powertrain control module 'A' - Bus signal/message failure - missing a message
( on 26-08-2017 10:22:09 at 238298 km )

Transmission

U2023-86 (A8 ) Control module network signal calibration data - Bus signal/message failure - signal is invalid
( on 26-08-2017 10:22:09 at 238298 km )

Replace the fuel filter

Check the low pressure fuel pump. Should be 6-7psi

If it's low, the in tank pump is faulty
If it's OK, it's 99% assured to be the HPFP

That's great - thank you!

Quick response - I presume you mean to change fuel filter and see if that cures the problem?

Or is it part of the overall strategy of fixing?

Fuel filters are known for giving issues, and restricting fuel flow. It should be replaced with an OEM or genuine filter before doing anything, as a restricted filter can cause low LPFP readings