If the display function does not work, replace the meter unit.

Check 3-6: Neutral Indicator Light (LED) Inspection
Meter Unit Circuit (ZX1000J Model)Electrical Leads
A two-color lead is identified first by the primary color and
then the stripe color. Unless instructed otherwise, electrical
leads must be connected to those of the same color.
Instrument
Use a meter that has enough accuracy for an accurate
measurement. Read the manufacture’s instructions ...
Front Fork Removal (Each Fork Leg)
Loosen the front fork top plug [A] beforehand if the fork
leg is to be disassembled.
Special Tool - Top Plug Wrench (45 mm) [B]: 57001-1741
NOTE
Loosen the top plug after loosening the handlebar
clamp bolt [C] and upper front fork clamp bolt [D].
Remove:
Upper Fairing Assembly (see Up ...
Hub Bearing Removal
Remove the wheels (see Front/Rear Wheel Removal),
and take out the following.
Collars
Coupling (Out of rear hub)
Grease Seals
Use the bearing remover to remove the hub bearings [A].
NOTICE
Do not lay the wheel on the ground with the disc
facing down. This can damage or warp the d ...