Closed-Circuit Current Measurement: Notes

Sporadically or continuously, an increased closed-circuit current can occur in the parked vehicle. Possible causes for that may be:

• An additional current consumer is connected to terminal 30 or the battery.
• Defective components, control units or control unit peripherals using too much power in sleep mode and preventing the vehicle entering sleep mode
• Automatic detection of the cause is not possible in the case of a closed-circuit current fault. On vehicles with an intelligent battery sensor, only the range of the quiescent current can be determined:
  • Quiescent current less than 80 mA
  • Quiescent current between 80 and 200 mA
  • Quiescent current between 200 mA and 1 A
  • Quiescent current above 1 A

Conclusions can be drawn as to the component causing the fault based on the amount by which the quiescent current limit is exceeded.