Royal Enfield Himalayan, Service Manual, Page: 179 / 214

ROYAL ENFIELD HIMALAYAN BS III VEHICLE SERVICE MANUAL
178
INSPECTION
STEP 1 :
Check the condition of the six diodes used in the RR Unit.
Take the Multimeter and change the mode to diode check mode. Diode mode would be available in continuity mode.
NOTE :
Before checking the diode, internal capacitor of RR unit to be discharged. Else, the diode drop will not be correct. So
short the positive and negative terminal of RR Unit DC output(black and red wires) to discharge the capacitor.
STEP 2 :
To check the condition of 3 positive diodes of RR unit, keep the positive probe (Red) of the multimeter in any one of
the 3phase terminals (yellow wire inserted in black/red connector) and the negative probe (Black) of multimeter on
the positive terminal of DC output (red wire inserted in two pole connector) and check for the condition of diode as
shown in the below image.
If the diode is good, then the multimeter will show a voltage drop of 0.4~0.7V.
If diode has failed, multimeter will show either open or short with beep sound, then Replace the RR unit.
3 Phase AC Terminals
RR UNIT