Hello everyone,

I'm creating this topic because I find myself at an impasse with my 2010 DISCOVERY 4 SDV6 (BVA6) with 240,000 km.

Let's start from the beginning: the engine failed on the highway (August 2023).
Since engine removal was planned for the repair, I decided to replace all the important parts (injectors, turbo, EGR, water pump, etc.). After reassembly, a transmission issue was detected, so the torque converter was replaced. However, the problem persisted, so the decision was made to perform a full rebuild of the BVA6 ZF transmission.

Once reassembled, the engine runs fine, gears shift smoothly (P-D-N-R +/-), high/low ranges engage properly, the compressor works well, and there are no mechanical noises.
BUT, after a while, the engine shuts off.


The engine stops either while driving or when parked once it reaches a certain temperature. I'm unsure whether this corresponds to the engine oil temperature or the transmission oil temperature.

When the engine shuts off, it restarts fine but with error codes, which makes me rule out an engine issue.
Voltages are good.

The TCU (Transmission Control Unit) has been replaced, wiring harnesses have been checked, grounds and the large copper strap have also been verified.
Soon, I will replace the ECU/PCM (the one behind the battery) to rule it out as the source of the problem.

PCM - ENGINE DIESEL 3.0L
P0700-00 - Transmission control system
(malfunction indicator lamp request) (2A)
À 237769 km
Déclenché le 04-12-2024 17:51:09



TCM-Transmission 6spd
U0100-00 - Lost communication with
engine control module/powertrain control
module 'A' (AA)
À 237768 km
Déclenché le 04-12-2024 17:49:16



TCCM- Transfer case
U0100-00 - Lost communication with
engine control module/powertrain control
module 'A' (2A)
À 237768 km
Déclenché le 04-12-2024 17:49:16

PCM-Engine Diesel 3.0L
P0700-00 - Transmission control system
(malfunction indicator lamp request) (2B)
À 237762 km

PBM-Parking Brake
U0100-00 - Lost communication with
engine control module/powertrain control
module A' (2B)
À 237768 km
Déclenché le 04-12-2024 17:49:16

ABS-Brake Module
U0100-00 - Lost communication with
engine control module/powertrain control
module 'A" (AB)
À 237768 km
Déclenché le 04-12-2024 17:49:16

BCM-Body Control
U0100-00 - Lost communication with
engine control module/powertrain control
module 'A' (2A)
À 237768 km
Déclenché le 04-12-2024 17:49:16



And that’s my little Christmas story.

Of course, I will update this post as things progress, but in the meantime, do you have any ideas or suggestions?

Thank you for reading and for any insights you can provide.

Wishing you a great day and a Merry Christmas!

Armand

 

I don’t have any insight to offer, but I just wanted to say that I am wishing for you to receive a Christmas miracle this year!!!

You deserve one with all that you’ve put into this vehicle, you must really love it!!

 

I concur.

However, the “lost communications” issues are typically the result of a battery in poor health, (thus insufficient power to activate modules)
Or the connections to/from battery in a poor state,

(Incidentally, this is Pinpoint Test #1)

Most are quick to report “the battery is new”. Which happens to be entirely irrelevant.
Some report on the voltage when the engine is running. Again, for testing a battery, irrelevant.
And others report “voltages are good”. Guess what… Irrelevant.
Battery voltage with engine not running and battery not connected to any charging source for 6 hours must be ascertained.
It should read 12.6 v.
If it reads 12.5, charge it. Wait 6 hours. Check voltage again.
If it reads 12.4v. Stop wasting your time and replace it with a fully charged battery in good health.

Once we pass pinpoint test 1, we can then move to other tests.

Are these ALL the thrown DTCs?

Cheers.