Bryant ASPAS1BBA015 - Manual (Page 101)

SECTION 4.4
DIAGNOSTIC TESTS
2. Connect the positive (+) meter test lead to the Wire 13
connector. Connect the negative (-) meter test lead to a
clean frame ground. Batter y voltage should be
measured.
3. Connect the positive (+) meter test lead to the Wire 16
connector. Connect the negative (-) meter test lead to a
clean frame ground.
4. Set the Auto-Off-Manual switch to MANUAL. Observe
the meter reading. Battery voltage should measured. If
battery voltage is not measured, proceed to Step 5.
5. Set the VOM to it’s “R x 1” scale to measure ohms.
6. Connect one test lead to the Wire 0 connector. Connect
the other test lead to a clean frame ground.
CONTINUITY should be measured.
RESULTS:
1 If battery voltage is not measured in Step 2, repair or
replace wiring between starter contactor relay and fuse
(F2).
2. If battery voltage is not measured in Step 4 and
CONTINUITY is measured in Step 6, replace the starter
contactor relay.
3. If battery voltage is measured in Step 4. proceed to Test
49.
TEST 49- TEST STARTER CONTACTOR
DISCUSSION:
The starter contactor (SC) must energize and its
heavy duty contacts must close or the engine will not
crank. This test will determine if the starter contactor
is in working order.
PROCEDURE:
Carefully inspect the starter motor cable that runs
from the battery to the starter motor. Cable
connections must be clean and tight. If connections
are dirty or corroded, remove the cable and clean
cable terminals and terminal studs. Replace any
cable that is defective or badly corroded.
Use a DC voltmeter (or a VOM) to perform this test.
Test the starter contactor as follows:
1. Connect the positive (+) meter test lead to the starter
contactor stud (to which the red battery cable connects).
Connect the common (-) meter test lead to a clean
frame ground. Battery voltage (12 volts DC) should be
indicated.
2. Now, connect the positive (+) meter test lead to the
starter contactor stud to which the starter motor cable
attaches (see Figure 6 or 7). Connect the common (-)
test lead to frame ground.
a. No voltage should be indicated initially.
b. Set the Auto-Off-Manual switch to MANUAL.
The meter should now indicate battery voltage
as the starter contactor energizes.
Figure 6. The Starter Contactor (Single Cylinder
Units)
Figure 7. The Starter Contactor (V-twin Units)
DC CONTROL
PART 4
Page 101