C5 battery eco mode problem

[tadleymansions]

Hi. C5 2.0 HDi tourer auto bought 2nd hand.
In my ownership there seems to be a problem with the eco mode battery saving system.
For example:-
After 100 mile round trip and standing overnight the electric tailgate will only operate once and then not operate few minutes later.
When parked up (ignition off) the radio only operates for a few minutes as do the windows and wipers etc.

Battery replaced 18 months ago because of this and there has not been any change.

Yesteday a 70 mile motorway trip and car parked for 5/6 hours battery down to 12.3 and took full charge when car started.

Yet in July car was left for a good 2 weeks and started first time.

The tailgate thing is the only real inconvenience but is now bugging me as I feel there is something wrong but don't know where to look

Battery is a Varta Silver E44.

John

[GiveMeABreak]

Hi and welcome John.

Unfortunately it may be something you'll have to live with. I too never get any more than a few minutes on economy mode. The system is supposed to give you double the time the car has been running - up to a max of 30 minutes, but never does - even with a new battery. If you have your VIN I can check if you have the Battery Charge Status Module fitted too.

Most of these units have been replaced with a different unit - from about February 2011. I was going to do mine - but hacking away at the battery wires put me off, so left it. I have a saloon, so can live with it as is, but with a Tourer it can be pretty frustrating. Anyway I can confirm which you have from your VIN.

[tadleymansions]

Hi Marc,
I did respond yesterday but obviously did not do it right as it is not in the thread.

Thanks for the quick response.

My VIN is VF7**************[VIN obfuscated, can be read by forum staff]********

John

[GiveMeABreak]

Ok, so you do have one of these little beauties John.

The biggest problems with these units (and I cannot say that any of the replacement units would make any difference) is the tailgate issue for estate owners. It is well known that the unit is too sensitive and adversely affects those with electric tailgate units.

Although I do not have the Tourer, I am currently undertaking a test of a procedure that may circumvent the unit - I will report back later....

[moizeau]

Can you not put it into 'showroom mode'? I thought this turns the eco bit off?

[Paul-R]

I think it turns damn near everything off! It certainly isn't useable for a road-going vehicle.

[tadleymansions]

Thanks Marc. Hope the "fix" works.
John

[GiveMeABreak]

Can you not put it into 'showroom mode'? I thought this turns the eco bit off?

Not really practical Pete, as that requires a special showroom harness and a shunt to do - which must be removed for a road used vehicle.

Although it's a clever box of tricks, it was badly designed for all the kit. I'm just going out to the car now to see if my theory is correct and will update shortly...

[GiveMeABreak]

Thanks Marc. Hope the "fix" works.
John

I'm pleased to report it has and I'm just writing the procedure up - but typically, got so carried away, I forgot to write down all the steps , so I'm back out to repeat it and then I'll pop it up with a few pics.

[GiveMeABreak]

Ok, so sorry about the wait - it took a while to write up - you know me - brief as always

The fix is in the Resources section for donating members:

Economy Mode Fix Procedure (C5 X7)

[MikeT]

Is it easy to remove/uninstall the BECB altogether?

[GiveMeABreak]

No not really Mike - it is wired onto the Negative cable and there isn't really a need to do that now as the parameter can accept it as present but delegate the function to the BSI. I would not recommend removing it as the system may still expect it to be there doing it's other stuff, with the exception of the economy mode triggering.

[MikeT]

No not really Mike - it is wired onto the Negative cable and there isn't really a need to do that now as the parameter can accept it as present but delegate the function to the BSI. I would not recommend removing it as the system may still expect it to be there doing it's other stuff, with the exception of the economy mode triggering.

Assuming it has the same diserable effect, your solution is more elegant. Kudos to finding that option, Marc.
BTW, can you view any of the live parameters it's sensing?

[tadleymansions]

Thanks Marc. All I need now is a VCI with Diagbox

John

[Hell Razor5543]

Well, I live in the Reading area, and I have a Lexia. Mind you, I am not sure how to help with your issues, so all I could do is read the error codes.