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Fused Components



Special Tools
140 589 13 21 00 Quiescent current test adapter 2
201 589 00 99 00 Electrical connecting set
140 589 12 21 00 Quiescent current test adapter 1






Commercially available tools)


1 Ascertain the possible quiescent current consumers on the problem fuse. See Electric Wiring Diagrams.

2 Unplug connector on possible quiescent current consumer.

3 Read off quiescent current on second multimeter.


NOTE: If measuring at the fuse for the radio, or if the radio connector is unplugged, it must be noted that the quiescent current consumption rises by approx. 0.240 A (240 mA) when the radio is reconnected.
This increase in quiescent current disappears when the battery is switched on and off again.


NOTE: In vehicles with auto-pilot system (APS), an increased quiescent current consumption of approx. 800 mA occurs after insertion of the APS computer fuse for the duration of the computer boot-up procedure (approx. 30 min). This also applies if the computer connector is unplugged and reconnected.


Quiescent current >0.02 A (20 mA):
Quiescent current fault remains after connector is unplugged.
Component is in order. Reconnect tested component.

4 Conduct test as described with all components on the problem fuse.

Quiescent current <=0.02 A (20 mA):
Quiescent current fault is rectified after connector of relevant component is unplugged. Component defective. Replace: (down arrow)

To check results, test total quiescent current again.