Computer System Service Precautions

The computer system is designed to withstand normal current draws associated with vehicle operation. However, care must be taken to avoid overloading any of these circuits. In testing for opens or shorts, do not ground or apply voltage to any of the circuits unless instructed to do so by the diagnostic procedures. These circuits should only be tested using a Digital Multimeter (DMM) if they remain connected to one of the computers. Power should never be removed or applied to one of the computers with the ignition switch in the ON position. Before removing or connecting battery cables, fuses, or connectors, always turn the ignition switch to the OFF position.