Generac Power Systems 53187 - Manual (Page 135)

PARTS
ENGINE ELECTRICAL SYSTEM
1
Test 6- Check for Battery Voltage at Ter­
minal 7 of Circuit Board (Continued)
PROCEDURE (CONT’D);
3. Now , connect the positive (+) VOM test lead to circuit
board term inal 7; the com m on (-) test lead to circuit
board term inal 2 (ground).
4. Hold the starVstop sw itch at “Start”. Crank relay
(CR1) should energize and the m eter should indicate
battery voltage.
RESULTS;
1. If battery voltage is NOT indicated in Step 4, go to
Test 8.
2. If battery voltage IS Indicated in Step 4, go to Test 7.
SECTION 5.9
TROUBLESHOOTING TEST PROCEDURES
a. Connect the m eter's positive (+) test lead to the
starter cable (W ire 16) term inal lug at the starter
contactor; connect the com m on (-) test lead to fram e
ground.
b. Hold the start/stop sw itch at "Start”. The m eter
should indicate battery voltage and the engine
should crank.
RESULTS;
1. In Step 5b, if battery voltage is indicated and the
engine cranks norm ally, discontinue tests.
2. If battery voltage w as indicated in Step 4, but is NOT
available in Step 5b, replace the starter contactor.
3. If battery voltage w as indicated in Step 5b, but the
engine does not crank, go on to Test 11.
Test 7- Test Starter Contactor
DISCUSSION;
During a crank attem pt, the crank relay (CR1)
should energize and its contacts should close to (a)
deliver battery voltage to circuit board term inal 1, and
(b) connect circuit board term inal 3 (W ire 17A) to
ground. The circuit board should then react by deliver­
ing battery voltage to a starter contactor coil. On closure
of the starter contactor contacts, battery pow er should
be delivered to the starter m otor and the engine should
crank. Failure of the starter contactor to energize or
failure of its contacts to close w ill result in a failure of
the engine to crank.
DANGER: Stand clear of all m oving parts w hile
perform ing this test. The engine could crank
and start at any tim e during the test.______________
PROCEDURE:
1. Set a VOM to read battery voltage.
2. Connect the positive (+) m eter test lead to the W ire
56 term inal of the starter contactor (see Figure 2).
Connect the com m on (-) m eter test lead to fram e
ground.
3. Hold the start/stop sw itch at "Start". USE CAUTION,
THE ENGINE MAY CRANK. The m eter should read
battery voltage and the starter contactor should ener­
gize.
a. If battery voltage w as Indicated in Step 4 of Test
6, but is NOT indicated now . W ire 56 (betw een the
circuit board and the starter contactor) m ust be open.
Repair, reconnect or replace W ire 56 as needed.
b. If battery voltage is indicated, but engine did not
crank, go on to Step 4 of this test.
4. Locate the large term inal lug on the starter contactor
to w hich the battery cable (W ire 13) attaches. Use the
VOM to m ake sure battery voltage is available to this
lug.
a. If battery voltage is NOT available or appears low ,
repeat Tests 2 and 3.
b. If norm al battery voltage is available, go on to Step
5 of this test.
5. Now , locate the large term inal lug on the starter
contactor to w hich the starter cable connects. Test
starter contactor operation as follow s:
Test 8- Test Start/Stop Switch
DISCUSSION;
Cranking and startup is initiated w hen the start/stop
sw itch is held at "Start" position. Setting the sw itch to
"Start" connects crank relay coil to ground, to energize
that relay. A defective start/stop sw itch can prevent the
engine from cranking.
DANGER: Stand clear of m oving parts w hile
perform ing this test. The engine m ay crank and
start at any tim e.________________________________
PROCEDURE;
Battery voltage should be available to the W ire 17
term inal of the start/stop sw itch at all tim es. Cranking
is initiated w hen closure of the sw itch contacts con­
nects W ire 17 to ground. To test the start/stop sw itch,
proceed as follow s (see Figure 3):
1. Use a VOM to check for the presence of battery
voltage at the W ire 17 term inal of the start/stop sw itch.
If not available, check W ire 17 betw een crank relay
(CR1) and the start/stop sw itch.
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