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 FAQ #87
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Economy mode C4 Coupe, Hatch and C4 Picasso


Economy mode can be frustrating but it is there to preserve battery life and stop it draining.

From Citroën's Technical Guide:

Consumption mode : "nominal" or "economy"

In nominal mode all the electrical functions are authorised .

If the alternator operational information has been present for less than 2 minutes and 30 seconds, the nominal mode remains active for a timing of 5 minutes .

If the alternator operational information has been present for more than 2 minutes and 30 seconds, the nominal mode remains active for double the alternator operating time and at the most for 30 minutes .

Example : to have a timing in nominal mode of 30 minutes, the alternator must have been operational for 15 minutes

Conditions for change to economy mode

Vehicle stopped or ignition key removed > The 30 minutes timer starts counting down only if the so-called reawakening or retaining functions are active.

Ignition on > The 30 minute timed period is counted down independently of the reawakening functions or permanent functions.

The "economy" consumption mode is available only when the alternator is not operating (engine not running) .

Economy mode prevents the battery from discharging when the engine is not running .

The non-permanent electrical functions are deactivated whatever the position of the ignition key .

Only certain permanent functions and some of the permanent requested locked functions are authorised in economy mode .

N.B. : A permanent function keeps operating even in the absence of the user .
N.B. : A permanent function requested locked keeps operating as long as the command is maintained .


Permanent functions authorised in economy mode :

· Hazard warning lamps
· Alarm
· Central locking

Permanent requested locked functions authorised in economy mode :

· Horn
· Indicators
· Headlamp flash

Passing from economy mode to nominal mode

Customer mode > Only if alternator operational or engine running information appears

Factory mode > Nominal mode can be activated by the diagnostic tool for a determined time or until it is stopped by the operator. When the engine running information appears at the BSI 1 . there is return to economy mode as soon as the engine running information disappears.


However there are some reported differences on the Picasso and Grand Picasso

BigJohnD wrote ...
C4 GP Exclusive wrote ...
Economy Mode usually kicks in after about 4 minutes on my C4GP.

I've been looking further, and it seems the C4 Pic is slightly different from the C4 Berline/Coupe in that it has a " Battery charge status control unit"

The Battery charge status control unit is a parameter in determining when Economy Mode kicks in -

"The economy mode is activated and determined in relation to the time remaining on the economy mode time counter or in relation to the battery charge status (threshold above 70%). The maximum economy mode time is 30 minutes"


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I've over simplified it as the Battery charge status control unit is very complex:

The main function of the battery charge status control unit (BECB) is to calculate the battery charge status, from measured (voltage, current) and calculated (battery internal temperature) physical parameters, then to transmit this information to the built-in systems interface to refine the activation of the energy economy mode .

The battery charge status control unit (BECB) incorporates an autodiagnostics function which returns any faults detected on the sensors and/or the internal electronics of the control unit .

The battery charge status control unit (BECB) has a role which permits optimisation of the management of the electrical energy .

When the generator is operating, the battery charge status control unit (BECB) permits optimisation of the load shedding strategies and when the generator is not operating, it permits provision of the comfort services (manual raising/lowering function, secondary inflation, maintaining of a comfortable temperature in particular) .

The battery charge status control unit :

Monitors the battery voltage in the off and ignition on statuses

Monitors the battery current in the off and ignition on statuses

Monitors the battery temperature in the off and ignition on statuses

Determines the battery charge status on the off and ignition on statuses

Determines the battery health status in the off and ignition on statuses

Informs the BSI 1 of an insufficient battery charge status

Informs the BSI 1 of a critical battery health status

The battery status sensor is supplied by a protected permanent battery+ supply .

The battery status information is available and distributed by the battery status sensor at the request of the built-in systems interface during the following life phases :

At the wake-up of the BSI 1 alone

At the partial and main wake-up of the IS CAN

At the wake-up of the COMFORT CAN or BODY CAN
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So it isn't random but pre programmed in. That's not to say like any software, it can't have a bug

The moral seems to be check your battery first - any thing less than perfect means Economy Mode will kick in in seconds.

Don't think we've had any complaints about short eco mode times here... but reading above it seems to be all Exclusive C4P/GP owners..... which I think the majority, if not all, are fitted with the Battery Charge Status Control Unit as described above.

Either that or the cars has for some reason gone into factory mode:- (click the image to enlarge)

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FAQ Posted by Road Runner
Info Created: 07 July 2008
Last Updated: 22 February 2014