Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

(Some people have issue connecting. LEMON is investigating. For now, use Firefox or change your DNS server)

Or, hide this message: temporarily or permanently

Oscilloscope Patterns and Waveforms




MEASUREMENT METHOD
Connect the analyzer special patterns pick-up to the generator B terminal.







STANDARD WAVEFORM
Observation Conditions





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.
In addition, if the ripples are abnormally high (more than approximately 2 V when the engine is idling), the cause is probably an open circuit between the generator B terminal and the battery due to a blown fuse, and the generator itself is usually okay.




ABNORMAL WAVEFORMS EXAMPLES

NOTE:
1. The size of the waveform patterns differs largely, depending on the adjustment of the analyzer's variable knob.
2. Identification of abnormal waveforms is easiest with a large output current (regulator not operating). These waveforms can be observed when the headlights are on.
3. Check the condition of the charging warning light (illuminated/not illuminated).