If any is worn down to the service limit, replace the brush assy.
Starter Motor Brush Length [B] Standard: 12.05 mm (0.4744 in.) Service Limit: 6.55 mm (0.258 in.)

Starter Motor Assembly
Commutator Cleaning and InspectionCAN Communication Line
CAN Communication Line
Resistance Inspection
In this model, resistors for CAN communication line are
built in the ECU [A] and meter unit.
Refer to the Meter Unit Inspection in the Electrical System
chapter for the resistor in the meter unit.
Turn the ignition switch to OFF.
Remove:
EC ...
Lights and Switches Operation Inspection
First Step
Set the gear position in the neutral position.
Turn the ignition switch to ON.
The following lights should go on according to below table.
If the following light does not go on, inspect the meter
unit (see Meter Unit Inspection in the Electrical System
chapter).
...
Alternator Rotor Installation
Using a cleaning fluid, clean off any oil or dirt on the following
portions and dry them with a clean cloth.
Crankshaft Tapered Portion [A]
Alternator Rotor Tapered Portion [B]
Install the alternator rotor.
Using a cleaning fluid, clean off any oil or dirt on the
washer [A] ...