Normal Sleep Mode
Normal Sleep Mode
- When the ignition is switched "OFF" (KL 0), the Busses go to sleep in 2 minutes.
- After 16 minutes, the Power Module sends a signal for the consumer circuits-roof zone (VA-D) shut-down and briefly wakes the Busses.
- VA-D is switched off and the Busses resume sleep mode.
- After 60 minutes, the consumer circuit-body (VA-K) is switched off.
The Power Module now assumes closed-circuit current monitoring mode:
- Cyclic voltage measurement every 5 seconds, cyclic current measurement every 60 seconds.
NOTE: If an operation is performed on the vehicle before 60 minutes has elapsed (central locking, trunk opened), the timer starts again from the beginning.
- Once the 60 minute period has ended, the closed-circuit current is approximately 30 mA (max. 50 mA).
- If the closed-circuit current exceeds 80 mA, the Power Module will monitor a 5 minute "waiting period" allowing the vehicle an opportunity to resume the normal 30 mA closed- circuit current.
- If the excessive current remains after the 5 minute waiting period, a fault code with the current value is stored. The Power Module issues the "Shutdown Counter" message and after 90 seconds, the vehicle's electrical system is shut down (briefly isolated) by the Electronic Battery Master Switch.
A second attempt is made and if excessive current draw is still present, the Shutdown Counter functions again after 90 seconds to isolate the electrical system.
The Electronic Battery Master Switch is reconnected under the following conditions:
- Change ignition from "OFF" to KL R or KL 15
- Toggling of the Battery Switch (switching back and forth twice within 2 seconds)
- KL 15 wake-up line (from CAS)
- External charge detection (> 13.2 V at the Power Module)
- CAN message relating to activated, legally required electric loads (hazard warning lights)
When the signal "15w" from the CAS is detected. the Electronic Battery Master Switch is closed and the following Check Control message is displayed:
Closed-circuit current monitoring is automatically cancelled by a message from the Lamp Module that the hazard warning lights are active.
When KL R is switched off, current monitoring is also immediately activated. Normal current load on the vehicle drops in stages according to the vehicle programming for sleep mode.
If the monitored current is > 120 amps (even as a random spike) the interior lighting, roof area consumers and body zone consumer circuits are immediately switched off.
Reasons for Electronic Battery Master Switch Disconnection
The reason for battery disconnection is stored together with the fault code in the Power Module fault memory. Several examples that may be stored are:
- The battery was disconnected because a current > 120 Amps was measured after switching off KL R.
NOTE: The current threshold was increased from 35 Amps to 120 Amps because all four power window motors can be operated simultaneously up to the end stop.
- The battery was disconnected because an excessively high vehicle closed-circuit current was measured.
- The battery was disconnected after a 3 week parking period.
- The battery was disconnected by activation of Storage Mode with the Battery Switch.
- The battery was disconnected because the battery capacity (SOC) dropped below the start limit with KL R switched on and KL 15 switched off.
- The battery was disconnected because a short-circuit in KL 30 was detected.
- The battery was disconnected by a DISplus/GT1 diagnostic command.
Closed-Circuit Current Monitoring And Vehicle Sleep Mode
