2. Checking the negative terminal of the rectifier: Using an ohmmeter, check that the circuit between the terminal of the "negative" diodes of the rectifier unit and the terminal of the stator winding is closed (resistance is low). Reverse the polarity of the ohmmeter probes and measure the resistance. If the resistance is low, i.e. the circuit is closed in both directions (diode is broken), replace the rectifier unit assembly.
3. Diode Test: Test the three diodes by connecting an ohmmeter to both terminals of each diode. If the circuit is closed or open in both directions at the same time, this means the diode has failed and the rectifier unit must be replaced.
