Test 47 - Test Starter Contactor Relay; (V-Twin Only); Test 48 - Test Starter Contactor - Generac Power Systems 7 kW NG Repair Manual

ENGINE/DC CONTROL
OUTPUTS 1 - 8:
1 0 1 1 0 0 0 1
Figure 112. The Home Page, Debug and Output Screens
Results
1. If the VOM indicated battery voltage in Step 4, refer back
to the flow chart.
2. If the Digital Output in Step 5 did not change, replace the
controller.
3. If the VOM did NOT indicate CONTINUITY in Step 11,
repair or replace Wire 56 between the J4 connector and
the relay or contactor.
TEST 47 – TEST STARTER CONTACTOR
RELAY (V-TWIN ONLY)
Discussion
The starter contactor relay (SCR) located in the control panel
must energize for cranking to occur.
normally open contacts of the SCR will close and battery
voltage will be available to Wire 16 and to the starter contactor
(SC).
Procedure
1. Set a Volt-Ohm-Milliammeter (VOM) to measure DC
voltage.
2. Disconnect Wire 13 from the SCR located in the control
panel.
3. Connect the positive meter test lead to Wire 13 and
connect the negative meter test lead to a clean frame
ground, measure and record the voltage.
4. Reconnect Wire 13 to the SCR
5. Disconnect Wire 16 from the SCR.
PART 4
DEBUG
OUTPUTS
OUTPUT 6
Once energized the
16
13
56
0
Figure 113. Starter Contactor Relay (V-twin Units)
6. Connect the positive meter test lead to the SCR terminal
from which Wire 16 was removed and connect the
negative meter test lead to a clean frame ground.
7. Set the AUTO-OFF-MANUAL switch to the MANUAL
position, measure and record the voltage.
8. Set the VOM to measure resistance.
9. Disconnect Wire 0 from the SCR.
10. Connect one meter test lead to Wire 0 and connect the
negative meter test lead to clean frame ground, measure
and record the resistance.
Results
1. If battery voltage was NOT measured in Step 3, repair or
replace Wire 13 between the SCR and the SC.
2. If battery voltage was NOT measured in Step 7 and
CONTINUITY was measured in Step 10, replace the SCR.
3. If CONTINUITY was NOT measured in Step 10, repair or
replace Wire 0.
4. If battery voltage was measured in Step 6 and CONTINUITY
was measured in Step 10, refer back to flow chart.
TEST 48 – TEST STARTER CONTACTOR
Discussion
The coil in the starter contactor (SC) must energize and its
normally open contacts close or the engine will not crank. This
test will determine if the SC is working.
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.
Section 4.5
Diagnostic Tests
16
13
COM NO
56 0
Page 119