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):
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:
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”).

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.

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 unauthorized 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 module reset):
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 (immobilizer) 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 unauthorized 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.
or
Waking:Lighting, for example of the START-STOP button, goes out briefly and on again.
Note:
If the vehicle does not go into the idle state for a sustained period, it must be determined which bus or which control module is waking the vehicle without motivation or is preventing it from sleeping.
Procedure: