Test 6A - Low Or High Battery
WARNING: This page is about a different car, the 1995 Dodge Dakota. However, it is still accessible from the selected car via links, so may be relevant.
Using an external voltmeter, check battery voltage. If battery voltage is 11.7-13.0 volts, replace scan tool. Perform TEST VER-1. If battery voltage is not 11.7-13.0 volts, repair charging system as necessary.