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

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Component Tests and General Diagnostics




Generator Oscilloscope Information

Oscilloscope - Reference Images

Test generator with oscilloscope (connect as for voltage measurement to B+ and generator housing.

Generator Images

Generator without Error






Generator with Phase Error






Generator with Diode Error (Plus or Minus Diode Break)






Generator with Diode Error, Plus or Minus Diode (Short Circuit- Generator Excited)






Generator with Diode Error, Plus or Minus Diode (Short Circuit- Generator Not Excited)






Instruction for Static Current Measurement

Impermissible high battery discharge may also result from drawing of an increased static current.

Drawing of the static current is dependent on:

* Vehicle equipment

* Control module tracking time