Standard Waveform
WARNING: This page is about a different car, the 2005 Mitsubishi Endeavor. However, it is still accessible from the selected car via links, so may be relevant.
NOTE:
The voltage waveform of the generator "B" terminal can undulate as shown at left. This waveform is produced when the regulator operates according to fluctuations in the generator load (current), and is normal for the generator. If the ripple height is abnormally high (approximately 2V or more during idling), the wires between the generator "B" terminal and the battery have broken due to fuse blowing, etc. The generator is usually operating properly.