Determine circuit with excessive quiescent current consumption - AR54.10-P-1030-04I

Fig 1: Identifying Electrical Connection Set (201 589 00 99 00)

Fig 2: Identifying Quiescent-Current Test Adapter 1 (140 589 12 21 00)

Fig 3: Identifying Quiescent Current Test Adapter 2 (140 589 13 21 00)

Fig 4: Identifying Multimeter Components

1. Check trunk illumination, if necessary replace defective parts and close trunk lid.
2. Unclip trunk illumination, detach insulated cable lugs and measure power consumption with multimeter (measuring range in amp (s)).

   After testing observe renewed run-on time of approx. 20 minutes.

   Total quiescent current q0.050A achieved, end of test.

   Specified value Total specified current  not achieved: ↓

3. Open fuse box in engine compartment (driver/front passenger) and fuse panel in rear (panel in rear right footwell illumination).

   With measurements on the fuse box in the rear, observe that the door contact switch is operated (e.g. with adhesive tape).

4. On vehicles with code (551a) anti-theft alarm system (ATA), operate engine hood contact (e.g. with adhesive tape).
5. Open overvoltage protection cover.
6. Lock vehicle.

   Observe Up-to-date Information (AI) bulletin! First of all, check circuits of the components which are listed in the Information Update.

7. Connect measurement cable (6) and test adapter (13) to a second multimeter (12) (measuring range in amp(s)).

   Remove the fuse for the ELECTRONIC ALARM SYSTEM only on unlocked vehicles (alarm signal).

8. Remove the first fuse and connect the second multimeter and read the standby current after 5 seconds.

   Standby current q0.020A (20 mA):

   The fuse-protected circuit is in order.

9. Insert fuse again and wait for 5 seconds.
10. Check quiescent current consumption at all fuses.

    After inserting the fuse or test adapter, the connected components can briefly exhibit an increased quiescent current, the radio up to 0.240 A (240 mA). By switching the radio on and off the standby current draw is raised.

On vehicles with navigation system after inserting the navigation computer fuse an increased quiescent current of approx. 800 mA occurs for the duration of the computer run-up (approx. 20 minutes).

Standby current >0.020A (20 mA): 

Wait for 20 minutes, then read off again.

The fused circuit is faulty: ↓

Determine fuse-protected components with increased quiescent current consumption.

The specific value of the entire standby current  is not  achieved: ↓

Determine non-fuse protected components with increased quiescent current consumption.