Closed Circuit Current Monitoring

Closed Circuit Current Monitoring For The E65/E66 Electrical System

In the event that an E65/E66 vehicle has a battery draw and/or the Power Module has faults stored in memory relative to closed circuit current monitoring, the following is provided to assist you in diagnosis.

Increased closed-circuit currents may occur permanently or occur intermittently, and cause the battery to discharge prematurely. The increase in closed circuit current may be caused by a faulty control module, or by the installation of a non-approved accessory.

In a situation where a vehicle has complaints due to a discharged battery, for diagnostic purposes it is important not to disconnect the battery. This is because a control module will be reset if the battery is disconnected. Following a reset, the faulty control module may start functioning correctly again, making accurate diagnosis impossible.

To correctly measure closed-circuit current, measurement adapter Special Tool P/N 90 88 6 612 300 should be used. This tool provides a bridge to ground, before the negative battery terminal is disconnected, and this prevents the control modules from being reset.

The additional use of MoDiC adapter Special Tool P/N 90 88 6 612 310 provides a method for current measurements over an extended period of time.

This procedure should be followed after you have reviewed the Power Module "Principle of Operation" in the beginning of this module.

Tools Required:







- 50 amp inductive probe for DISplus or MFK1 for the MoDIC/GT1.
- BMW closed circuit current measuring tool # 61 2 300 (4. in diagram).
- Digital Multimeter capable of measuring up to 15 Amps.
- MoDIC adapter # 61 2 310 for recording draws up to 72 hours (3. in diagram).