Honda Insight Owner's Manual page 328

Brake Fluid
Always use Honda Heavy Duty
Brake Fluid DOT 3. If it is not
available, you should use only DOT 3
or DOT 4 fluid, from a sealed
container, as a temporary
replacement.
Using any non-Honda brake fluid can
cause corrosion and decrease the life
of the system. Have the brake
system flushed and refilled with
Honda Heavy Duty Brake Fluid
DOT 3 as soon as possible.
Brake fluid marked DOT 5 is not
compatible with your vehicle's
braking system and can cause
extensive damage.
322
MAX
The fluid level should be between
the MIN and MAX marks on the side
of the reservoir. If the level is at or
below the MIN mark, your brake
system needs attention. Have the
brake system inspected for leaks or
worn brake pads.
MIN