Generac Power Systems 940-2 TEST 9- CHECK WIRE 56 POWER TO STARTER CONTACTOR, Starter Contactor

Models: 941-2 940-2

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Figure 5. Starter Contactor

Section 7.2

ENGINE DC CONTROL SYSTEM / AC TROUBLESHOOTING

This test will determine if battery voltage is available to the Starter Motor for cranking the engine.

TEST PROCEDURE:

1.Set a VOM to read battery voltage (12 VDC).

2.Connect the meter test leads across the starter terminal and frame ground.

3.Hold the Start-Run-Stop switch at "START". The VOM should read battery voltage and the engine should crank.

RESULTS:

1.If power supply is good and engine cranks, stop tests.

2.If power supply is good but engine does NOT crank, replace the Starter.

3.If power supply is bad, go on to Test 9.

4.If voltage drops during cranking (i.e. from 12 VDC to 9.5 VDC or lower), then check battery condition and cable sizes per the installation manual. Verify that proper grounding of the genera- tor exists.

3.Set the Start-Run-Stop switch to "START". The meter should indicate battery voltage.

RESULTS:

1.No power to Wire 56 terminal, go to Test 10.

2.If power to Starter Contactor is good, go to Test 11.

Figure 5. Starter Contactor

Figure 4. Starter Motor

TEST 9- CHECK WIRE 56 POWER TO

STARTER CONTACTOR

DISCUSSION:

When the Start-Run-Stop switch is set to "START", the A6060 circuit board must react by delivering bat- tery voltage to the Starter Contactor coil, via Wire 56. Without this battery voltage, the Contactor will not energize and battery output will not be delivered to the Starter Motor. The engine will not crank.

TEST PROCEDURE:

1.Set a VOM to read battery voltage (12 VDC).

2.Connect the meter test leads across the Wire 56 starter con- tactor terminal and frame ground.

TEST 10- CHECK A6060 CIRCUIT BOARD

POWER SUPPLY

DISCUSSION:

Fused battery voltage is delivered to the A6060 circuit board via Wire 15. If this power (12 VDC) is not avail- able to the board, cranking and startup will not be possible.

This test will determine if battery voltage is available to the circuit board for its operation.

TEST PROCEDURE:

Set a VOM to read battery voltage (12 VDC).

Connect one VOM test lead to the Wire 15 terminal J2-5 on the A6060 circuit board. Connect the other test lead to frame ground. The meter should indicate battery voltage.

RESULTS:

1.If battery voltage is NOT indicated, check Wire 15 between the 7.5 amp fuse and the A6060 circuit board. Repair, reconnect or replace the wire as needed.

2.If Battery Voltage was indicated, test for proper ground from the A6060 circuit board. Set a VOM to read Resistance. Measure from terminal J2-6 to the generator frame ground. A “Continuity” reading should exist. If open or high resistance is measured, repair wires or ground connections.

3.If 12 VDC was indicated, go to Test 12.

Page 7.2-12

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Generac Power Systems 940-2, 941-2 TEST 9- CHECK WIRE 56 POWER TO STARTER CONTACTOR, Starter Contactor, Starter Motor