Electrical System - Parasitic Draw Measurement: Overview

SI B61 08 00
General Electrical Systems

May 2012
Technical Service

This Service Information bulletin supersedes SI B61 08 00 dated December 2010.

[NEW] designates changes to this revision

SUBJECT
Closed-circuit Current Measurement

MODEL
All

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

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

[NEW] To correctly measure closed-circuit current, the 50-amp clip-on probe (previously used with the MIB) or the 100-amp clip-on probe can now be used in conjunction with the IMIB (Integrated Measurement Interface Box) to properly diagnosis closed-circuit current problems over an extended period of time. Connect the amp clip-on probe directly to the IMIB Measurement input 3 (green socket). Refer to SI B04 35 09 for information about the IMIB.

WARRANTY INFORMATION
Not applicable