Table 3-3. Unit Maintenance Troubleshooting Continued
TEST OR INSPECTION
Step 3. Check fuel filter.
Clean and inspect
described in table
fuel filter as
Step 4. Check fuel pump operation by checking for 24 V dc between fuel pump con-
nector and case.
If 24 V dc is present, replace fuel pump.
Step 5. Check fuel pump cable.
Disconnect cable from heater. Check fuel pump plug
for loose connections or damage.
Check cable wires for continuity:
Replace defective cable.
To remove and install plug, refer to REMOVE/
INSTALL POWER, FUEL PUMP, AND ROOM THERMOSTAT PLUGS,
Step 6. Check external fuel pump receptacle for damage. Inspect for burned contacts
and other damage.
Replace defective receptacle as described in lNSPECT/REMOVE/lNSTALL
POWER RECEPTACLE AND EXTERNAL FUEL PUMP RECEPTACLE,
Step 7. Check
Death or serious injury could occur if pre-
cautions are not taken when maintaining this
equipment. Be sure that any power cables
are unplugged/disconnected. Be sure that the
equipment is properly grounded. Always
have another person standing by who is
trained in electric shock first aid.
external fuel pump receptacle for 24 V dc.
If current is not present, forward heater to intermediate maintenance for
testing of PC board.