Guardian 4389 Repair Manual page 120

SECTION 4.4
DIAGNOSTIC TESTS
2) If coil resistance of 113 ohms was mea-
sured, the short is in Wire 194 between the
transfer relay and the terminal strip. Repair
or replace Wire 194.
5. Disconnect Wire 56 From the starter contactor relay
(SCR on V-twin) or the starter contactor (SC on single
cylinder). Connect one meter test lead to the SCR or
SC terminal from which Wire 56 was removed. Connect
the other meter test lead to the ground terminal. If CON-
TINUITY or zero resistance was measured, replace the
SCR or SC. Coil resistance for the SCR is 155 ohms.
Coil resistance for the SC is 4 ohms. If coil resistance
was measured, Wire 56 is shorted to ground between
Connector J1 and the SCR or SC. Repair or replace the
shorted wire.
6. Disconnect and isolate each Wire 14 from the 4-tab
insulated terminal block. Repeat Step 3 for Pin Location
J1-7. If CONTINUITY was measured, repair or replace
Wire 14 between Connector J1 and the 4-tab terminal
block. If INFINITY was measured, proceed as follows:
a. Disconnect Wire 14 from the following: fuel sole-
noid (FS), battery charge relay (BCR) and
hourmeter (HM) if equipped.
b. Connect the negative (-) meter test lead to the
ground terminal. Connect the positive (+) meter
test lead to each of the listed components at the
terminal from which Wire 14 was removed. If
CONTINUITY or zero resistance was measured,
the component has shorted to ground. Replace
the component. The average nominal resistance
value that should be measured for each compo-
nent is:
Battery Charge Relay (BCR) - 112 ohms
Fuel Solenoid (FS) - 31 ohms
Hourmeter (HM) - 2 Mega ohms to INFINITY
Page 118
PART 4
c. If each component tests good, there is no short
to ground. The fault exists in one of the Wire 14
wires. Connect one meter test lead to the ground
terminal. Connect the other meter test lead to
each Wire 14 individually (on the end removed
from the BCR, FS or HM). The Wire 14 which
measures CONTINUITY is shorted to ground.
Repair or replace the affected wire between the
component and the 4-tab terminal block.
TEST 77 - TEST EXERCISE FUNCTION
DISCUSSION:
The following parameters must be met in order for the
weekly exercise to occur:
• AUTO-OFF-MANUAL switch (SW1) set to AUTO.
• Circuit board DIP Switch 2 (Remote Not Auto) set
to OFF.
PROCEDURE:
1. Set the AUTO-OFF-MANUAL switch (SW1) to MANUAL.
The generator should start. Set SW1 back to AUTO.
Verify that SW1 has been in AUTO for weekly exercise
to function.
2. Verify that DIP Switch 2 (Remote Not Auto) on the cir-
cuit board is set to the OFF position (see Figure 1,
Section 1.6).
3. Hold the Set Exercise switch until the generator starts
(approximately 10 seconds) and then release. The gen-
erator will start and run for approximately 12 minutes
and then shutdown on it's own. The exerciser will then
be set to start and run at that time of that day each
week. If the unit does not start, go to Test 73. Retest
after performing Test 73. If the generator still will not
start, replace the circuit board. If the generator does not
start after depressing the Set Exercise switch, wait one
week and watch for exercise operation. If exercise fails
to operate, replace the circuit board.
DC CONTROL