Energy diagnosis: closed-circuit current monitoring

Closed-circuit current measurement

Procedure for external closed-circuit current measurement: See help document ”Observing sleeping with external closed-circuit current measurement” or Service Information number 610399474.

Identifying features for vehicle sleeping (idle [sleeping] state normally occurs after a maximum of 3 minutes):

Lighting of the START-STOP button goes out
Lighting of the switch blocks for seat adjustment goes out
Lighting of the child safety switch on the switch block on the driver's door (green LED) goes out

The duration of normal sleeping and regular consumer unit shutdown is up to 60 minutes after terminal R off. In order to shorten the time for troubleshooting in the event of closed-circuit current faults, there is the possibility to put the vehicle to sleep immediately using the Power Down command.

Power Down command: forced sleeping

In order to place the vehicle in the idle state, the following requirements must be met:

BMW diagnosis system connected
No battery charger connected
Remote control or identification sensor disconnected from insert compartment
The vehicle is still awake (maximum 2 - 3 minutes after terminal R off)

The Power Down command can then be sent with the corresponding test module or service function.

Important: the idle state is terminated on waking the vehicle up again, for example actuating the remote control, door-handle contact, etc.

If the identifying features (see above) indicates that the vehicle is asleep, a closed-circuit current measurement can be carried out after approx. 30 seconds. The total closed-circuit current must be < 80 mA.

Regular sleeping

If the identifying features (see above) indicate that the vehicle is asleep a total closed-circuit current of < 80 mA must be reached after approx. 60 minutes (see document ”Closed-circuit current characteristics”).

Terminal R Off. The vehicle goes to sleep after 2 - 3 minutes.
Regular waking for consumer unit shutdown after 16 minutes (consumer unit shutdown in roof and interior lighting by the power module).
Shutdown of consumer units in body by the power module after 60 minutes.

Note: If the engine has run for a period of time, two additional wakings are to be observed: 30 min and 70 min after terminal R OFF, KOMBI (instrument cluster) wakes the vehicle to query the coolant temperature. Both wakings are normal and do not lead to a fault code memory entry.

First waking by the KOMBI (instrument cluster) (check of the coolant temperature).
Second waking by the KOMBI (instrument cluster) (check of the coolant temperature).

Closed-circuit current fault

The power module starts with closed-circuit current monitoring approx. 60 minutes after terminal R off if the vehicle has gone to sleep in the regular manner and there has been no unauthorised waking in the meantime.
If a closed-circuit current fault is detected for 8 minutes, the power module switches the power supply of the following consumer units off for a few seconds (control unit reset):

All of the consumer units supplied by the power module except for the instrument cluster, LM, FBD receiver, CAS, DWA and DME/DDE.

If the closed-circuit current fault remains, after another 8 minutes the power supply of the above-mentioned consumer units is switched off permanently for this sleep cycle.

For vehicles as of date of manufacture 03.2005:
If there is still a closed-circuit current fault despite shutdown of the power supply to the consumer units, the following consumer units that have not yet been switched off are given a reset (10 seconds): KOMBI (instrument cluster), LM, FBD receiver, CAS and DME/DDE. This short cutoff only takes place if no active lighting function is registered.
The DWA (immobiliser) is not given a reset and/or the power supply is not cut off.

In order to pinpoint the cause, run a measurement at the high-voltage outputs on the power module (with the ammeter clip). In this way, it can be determined in which area the consumer unit is located: distribution box at front or rear.
At the corresponding distribution box, the cause can be determined by successively removing fuses.

If the power module was unable to reduce the closed-circuit current with shutdowns, please concentrate troubleshooting on the components supplied via terminal 30 (see list above).

Sleeping inhibited or frequent unauthorised waking

Inhibited sleeping:Lighting, for example of the START-STOP button (as identifying feature for activity on the bus systems), does not go out after a minimum of 2 - 3 minutes after terminal R off.

Waking:Lighting, for example of the START-STOP button, goes out briefly and on again.

Note:

The vehicle must normally go into the idle state with doors and bonnet/rear lid open!
As a rule, a fault (waking or inhibited sleeping) always keeps all bus systems awake or wakens them!

If the vehicle does not go into the idle state for a sustained period, it must be determined which bus or which control unit is waking the vehicle without motivation or is preventing it from sleeping.

Procedure:

For vehicles as of date of manufacture 03.2004, first run the energy diagnosis with the BMW diagnosis system.
For all vehicles:
- Read out the fault code memory and run the test modules for all fault code memory entries.
- To check which bus system is waking the vehicle, it might be necessary to unpin the corresponding data line of the various bus systems at the gateway (here: SGM-ZGM or ZGM) in order to test.
- Identify possible causes by successively disconnecting fuses or disconnecting the corresponding control units.
- In the case of vehicles with the optional extra Comfort Access, also disconnect the outside door handle electronics on all door in succession.
- After troubleshooting or fault elimination, make sure of the success by putting the vehicle to sleep a number of times and observing behaviour on sleeping!
- In order to avoid unnecessary part replacement, in cases of doubt, consult your technical advice department after running all of the measures described in this document.