Evening all!

Lara has been behaving herself recently so I have been lurking in the background, but yesterday she threw all her toy out and won't start.

She just shows HDC fault on the screen.

These are the fault codes.

ECU: ABS system CODE:U0401 Invalid data received from engine control module/powertrain control module (PERMANENT)

ECU: All Terain Control CODE:U0415 Invalid data received from ABS control module (PERMANENT)

ECU: Body Control CODE:C0023 Stoplamp control (INTERMITTENT)

ECU: Body Control CODE:B10A2 Crash input (PERMANENT)


I have looked for a second earth lead but I can't find it, But I put a jump lead from the negative on the battery to the bottom of the engine as a test, it didn't help.

I have checked the fuses under the bonnet.

And charged the battery as well as have her attached via a pair of jump cables to he V8 stable mate for extra power.

Put the key in and press the start stop button and just beeps and puts the HDC message up on the screen.

Anything else I can try before sending her to the mechanics?

Thanks in advance LJ & Lara the i6
Surrey 4x4 Response volunteer member

Try a hard reset. With that many codes they also need clearing out. FL2 MY10 TD4 GS traded in at 2 years
FL2 MY13 TD4 GS Current

The faults are typical for a flat battery. All associated with insufficient power to run the ABS which is the main physical input into HDC, Terrain Control and DSC. Even the Haldex needs electricity to work its clutch. My FL2 does this even with an extra earth lead from battery to starter mount bolt. Something didn't shut down properly the last time you left Lara or the battery has failed. It takes a really good charge to get mine going again. A partial charge and a jump start just doesn't do it and we end up in SWMBO's car, now a fiesta st3 so at least it's a fun drive

Could you use one of those portable battery packs to get it started. Would it be ok to use one of them?. Could come in handy of those unexpected flat battery days. I have one of those jumping jacks battery pack things and it would jump start a td5 defender. GS Sd4 2012

Just thought it was time for update...


And the winner was..... {drum roll}


The starter motor!

So now replaced and all toys returned to the pram. Seems the faults were just a product of not starting, not the other way!

Hope this helps someone else. Start with the basics, then move on to the more technical stuff.

Happy F2ing. LJ & Lara the i6
Surrey 4x4 Response volunteer member

Just out of interest does your car have stop/start? I once spoke to an AA guy who said that they had noticed an increase in starter motor failures after this feature become more common. 3 x FL1 2 manual + 1 auto
5 x FL2 4 manual + 1 auto
Now Discovery Sport P250 MHEV SE

Dorset, it you click on Lady Jane's Avatar you will see it is an 07 i6. (A rare breed 😉)

Bob 10MY (Sept 09) TD4 HSE Auto in Stornoway Grey (Now Gone)

08 FL2 TD4 SE Manual in Rimini Red (Now Gone)

No stop start, Lara is too old for it

Thanks dunkley201 yes she is a rare breed. LJ & Lara the i6
Surrey 4x4 Response volunteer member