HDC Inactive

Good evening everyone.
Just a quick bit of advice needed as I'm a newbie to the L322.
I have recently had the HDC warning message active on the LCD display, but only on start up from cold after I have not used the old girl for a day or 2.
My RR is a 2004, 3.0 TD6 Vogue.
I was told this could be due to a low battery due to her only being used a few times a week, the rest of the time she sits in the garage.
This warning only appears after the car has not been used for a few days.
Once started if you switch off after she has been running for a few minutes no warning at all.
I now have a trickle charge smart charger attached whilst not in use but still get this warning on cold start up after the pre-heating message appears. The message activates as soon as she fires up and goes out straight away. I have pushed the check control button and no warnings show.
Recently had service & MOT and nothing shown on the diagnostics.
Anybody else had this message appear.
Kind regards,
Mark.

Check the battery voltage before you start it.

I also have had that every cold morning in the last week, volts all ok, guess the lickle princess doesne like the cold mornings as I tested it and it does work

cossiedreamer1 said:

I also have had that every cold morning in the last week, volts all ok, guess the lickle princess doesne like the cold mornings as I tested it and it does work

Click to expand...

Cold weather always shows up a weak battery.

I had this issue, here's an article taken from another forum;

"HDC Inactive" Message - Fault Found

Took Range to Stealer this morning and I have to say I was impressed. Very helpful and honest.

Plugged Range upto computer and found No Codes stored in any of the ECU's.

They explained that the reason why the "HDC Inactive" Messages Displays.

Technical Service Bulletin No. LM206-002, 04 January 2005

Subject/Concern: Range Rover (LM) - HDC Inactive Message after Engine Start in Low Temperatures.

Models: Range Rover (LM) 2002 - 2006 Engine: TD6

Markets: All

Section: 206-09

Section: Brakes

Summary: In low ambient temperatures the "HDC INACTIVE" message may be displayed during and/or shortly after cranking the engine.

NOTE: HDC functionality is NOT effected, this is a message display error only.

Cause: Low batter voltage during engine cranking triggers the message display.

Action: Should a customer express concern regarding the above, refer to the Service Instruction detailed in this Bulletin in order to replace the anti-lock braking (ABS) electronic control unit (ECU)

Found something on another website a few weeks back, seems to be quite 'common' but can't find the article im looking for. There was something you could replace, but at a cost of about £1k if it wasn;t down to low voltage with the battery. It's not something that causes issues if you don't replace, you just get the error message from time to time upon startup.
I'll keep looking for the article....!!

Rob

you can replace the ABS ECU for an updated version that wont show the fault upon startup.

2.0_hippo said:

you can replace the ABS ECU for an updated version that wont show the fault upon startup.

Click to expand...

Ellis,

Would it still throw up a HDC fault with the later ABS ECU if battery voltage is low??

Regards
Rob

robhew86 said:

Ellis,

Would it still throw up a HDC fault with the later ABS ECU if battery voltage is low??

Regards
Rob

Click to expand...

it shouldn't do, hence the updated ECU that they say is meant to sort it.

either way, range rover's do very odd things when the battery is low

Thank you guys so much for your help, as I too suspected it is low battery voltage, as mine too didn't show any faults stored in the ecu. And after reading the LR. bulletin, my question is answered.
Thanks guys.