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

Check 3-6: Neutral Indicator Light (LED) Inspection
Meter Unit Circuit (ZX1000J Model)Exploded View
7. US, CA and CAL Models
8. Immobilizer System Equipped Models
9. ZX1000JD/KD
AD: Apply adhesive.
L: Apply a non-permanent locking agent.
R: Replacement Parts
13. Other than US, CA and CAL Models
CL: Apply cable lubricant.
EO: Apply engine oil.
G: Apply grease.
L: Apply a ...
KIBS Hydraulic Unit Inspection
Remove the KIBS hydraulic unit (see KIBS Hydraulic Unit
Removal).
Visually inspect the connector terminals [A].
Replace the KIBS hydraulic unit or main harness if either
of the terminals are cracked, bent, or otherwise damaged.
If the KIBS hydraulic unit connector is clogged with mud
or ...
Cylinder (Upper Crankcase) Wear Inspection
Split the crankcase (see Crankcase Splitting).
Remove the pistons (see Piston Removal).
Assemble the cylinder (upper crankcase) [A], the cylinder
head [B] and the cylinder head gasket [C].
Tighten the cylinder head bolts (see Cylinder Head Installation
in the Engine Top End chapter).
...