Direct Voltage Adaptor (Dva) Test - Mercury 75 Service Manual

Direct Voltage Adaptor (DVA) Test

CAUTION
DVA checks can be made while cranking engine
with starter motor. To prevent engine from start-
ing while being cranked, all spark plugs must be
removed.
CAUTION
To protect against meter and/or component dam-
age, observe the following precautions:
INSURE that the Positive (+) meter lead is
connected to the DVA receptacle on the
meter.
DO NOT CHANGE meter selector switch posi-
tion while engine is running and/or being
"cranked".
NOTE: Each CDM is grounded through the engine
wiring harness via the connector plug. It is not neces-
sary to have the CDM mounted on the ignition plate
for testing.
1. Remove all spark plugs.
2. Insert spark gap tool (P/N 91-63998A1) into each
spark plug boot and attach alligator clips to a
good engine ground.
3. Disconnect remote fuel line from engine.
4. Make sure all CDMs are plugged in.
2A-32 - ELECTRICAL
5. Test Stator and Trigger voltage to CDM:
a. Install test harness 84-825207A2 between
ignition harness and CDM.
c
a
b
a - Stator/Trigger Harness
b - Test Harness 84-825207A2
c - Capacitor Discharge Module
b. Test each CDM.
Red Stator Output Test
@ Cranking Speed
Positive Meter Negative
Lead (+) Meter Lead (–)
Connect to Connect to
Green Test Black Test
Harness Lead Harness Lead
If only one CDM stator reading is below specifica-
tions, replace that CDM. If all CDM stator voltage
readings are low, go to Testing Stator Resistance.
90-830234R3 DECEMBER 1997
400 DVA Scale
DVA
Reading
100 - 350