Mercury MerCruiser D2.8L D-Tronic Service Manual page 574

EDI DIAGNOSIS
3. When a test light is specified, a low-power test light must be used. Do NOT use a high-
wattage test light. While a particular brand of test light is not suggested, a simple test,
as shown below, on any test light will ensure it to be safe for system circuit testing:
a. Connect an accurate ammeter (such as the high impedance digital multimeter) in
b. If the ammeter indicates LESS than 3/10 amp current flow (.3 A or 300 mA), the test
c. If the ammeter indicates MORE than 3/10 amp current flow (.3 A or 300 mA), the test
NOTE: Using a test light with 100 mA or less rating may show a faint glow when test actually
states no light.
4. When using a DVOM to perform voltage measurements, turn the ignition OFF when
connecting the DVOM to the circuitry to be tested.
Page 5E-6
series with the test light being tested, and power the test light/ammeter circuit with
the battery.
light is SAFE to use.
light is NOT SAFE to use.
d - Amp meter
e - Test Light
f - 12 Volt Battery
b
a
SERVICE MANUAL NUMBER 22
c
90-860074--1 FEBRUARY 2002