Diagnostic Aids
WARNING: This page is about a different car, the 2002 Saturn LW200, 2002 Saturn L200, and 2002 Saturn L100. However, it is still accessible from the selected car via links, so may be relevant.
With ignition on, engine off, voltage measured with DVOM on Red wire at generator with connector disconnected should read 5 volts.
A generator that is not charging with engine running will pull Red wire (though resistance) to ground and set DTC.
An intermittent open or short to ground on Red wire will set this DTC. GENERATOR F TERMINAL DC on scan tool will read zero percent with ignition on if this occurs.
GENERATOR F TERMINAL DC on scan tool should read near 17 percent with ignition on, engine off.