Mazda 323 1988 Workshop Manual page 920

METER (INCL. SENDER UNITS) 15
3. Set the checker to the resistance values shown in
the figure.
4. Turn on the ignition switch and check to confirm
that the needle indicator disolavs the correct
values. If the needle displays the correct values,
the trouble is in the gauge unit; if not, the trouble
is in the meter.
5. When the meter indicates 18.8 * 3.0 ohms or less,
the segments will start flashing.
Note
a) Continue the above inspections for at least
two minutes each to correctly judge the
condition.
b)The allowable indication error is twice the
width of the needle.
Water Temperature Gauge Unit
1. Remove the gauge unit,
2. Place the gauge unit in a container of water, and
heat the water to 80% (178°F).
3. Use an ohmmeter to measure the resistance.
Resistance: 57.7-49.3 0
15-25