Check Fuel Pump; Test - Guardian Quietpact 55 Repair Manual

S S e e c c t t i i o o n n 7 7
D D I I A A G G N N O O S S T T I I C C T T E E S S T T S S
Figure 7-13. – The LPG Fuel Solenoid (FS)
RESULTS:
1. If battery voltage is not indicated in Step 2, check Wire 15 between
the Primer Switch and the 7.5 amp fuse for an open condition.
2. If battery voltage is indicated in Step 2 but not in Step 4,
replace the Primer Switch. If battery voltage is NOT indicated
in Step 3 repair or replace Wire 14 between the 4-tab Terminal
Connector (TC) and the Fuel Primer Switch (SW2).
3. If battery voltage was indicated in Step 4 but not in Step 5:
a. For gasoline models repair or replace Wire
14A between the Primer Switch (SW2) and
Fuel Pump Connector 2.
b. For LPG models repair or replace Wire 14A
between the Fuel Prime Switch (SW2) and
the LPG Fuel Solenoid (FS).
4. If the meter reads anything other than "Continuity" in Step 7,
replace the Primer Switch.
5. If the Primer Switch checks good, go to Test 20 for Gasoline
models. For LPG models, go to Test 42.
TEST 20- CHECK FUEL PUMP
DISCUSSION:
An inoperative Fuel Pump will (a) prevent the priming
function from working and (b) prevent the engine from
starting.
PROCEDURE:
1. Remove Fuel Filter and verify that filter is not clogged. Replace
filter if necessary.
2. Verify that fuel is available to Fuel Filter inlet. Use an alterna-
tive fuel supply if questionable.
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3. Remove air filter access panel and air filter. Remove fuel hose
from pump. Place a suitable container to catch fuel from fuel
pump line. Activate fuel primer switch. Pump should operate
and fuel should flow. If pump does not operate, proceed to
Step 4.
4. In Test 19, Battery Voltage was checked at Connector 2. This
step will test the ground wire. Disconnect Connector 2 at the
Fuel Pump. Set the VOM to measure resistance. Connect one
test lead to Wire 0, (Pin 1 of Connector 2) that goes to the
Control Panel (see Figure 7-12). Connect the other test lead to
a clean frame ground . "Continuity" should be measured.
5. To test for an open fuel pump coil, connect one test lead to the
Red Wire (Pin 2 of Connector 2) going to the fuel pump.
Connect the other test lead to the Black Wire (Pin 1 of
Connector 2) going to the Fuel Pump (see Figure 7-15). The
VOM should indicate Fuel Pump coil resistance of about 29.5
kW. (Current draw of the pump at nominal voltage is approxi-
mately 1.4 amperes MAXIMUM).
Short to Ground:
6. To test for a shorted fuel pump coil, connect one test lead to
the Red Wire (Pin 2 of Connector 2, see Figure 7-15). Connect
the other test lead to the fuel pump housing. "Infinity" should be
measured.
Figure 7-14. – Electric Fuel Pump
RESULTS:
1. If "Continuity" was not measured in Step 4, repair or replace
Wire 0 between Connector 2 and the ground terminal.
2. If "Continuity" is measured in Step 4, but pump does not oper-
ate in Step 3, replace the Fuel Pump.