Honda 1997 Civic Sedan Online Reference Owner's Manual page 159

Lights
HORIZONTAL ANGLE GAUGE
3. Open the hood.
4. Check the horizontal angle gauge.
The line on the adjustment screw
indicator should line up with the
"0" mark on the gauge.
Maintenance
VERTICAL ANGLE GAUGE
5. Check the vertical angle gauge.
The bubble should be centered
underneath the longest scribe
mark on the gauge.
HORIZONTAL ADJUSTMENT
BUBBLE
6. If either indicator is not aligned
with its "0" mark as described, an
adjustment can be made using a
Phillips-head screwdriver to
realign it with the "0" mark. Please
refer to the illustrations.