
TROUBLESHOOTING AND ELECTRICAL SYSTEM
Test Procedures
Page 11-38
2005 FE350 Gasoline Vehicle Maintenance and Service Supplement
11
Test Procedure 25 – Battery Test (Under Load), Continued:
6. If the reading is zero, there may be no continuity across the large posts of the solenoid.
See Test Pro-
cedure 7 – Solenoid on page 11-21.
7. If all of the test results are good and the voltage reading is zero, there may be a broken or damaged 6-
gauge white wire from the solenoid to the starter/generator.
See Test Procedure 9 – Starter/Generator
(Starter Function) on page 11-23.
TEST PROCEDURE 26 – FUEL LEVEL SENDING UNIT
See General Warning, Section 10, Page 10-1.
ý
WARNING
• To avoid the possibility of fire or explosion, make sure the fuel tank cap is securely in place
while performing this test procedure.
1. Disconnect the battery cables as instructed.
See WARNING “To avoid unintentionally starting...” in
General Warning, Section 10, Page 10-1.
2. Disconnect the orange wire from the center post of the fuel level sending unit.
3. With a multimeter set to 2 k ohms, place the red (+) probe of the multimeter on the center post of the
sending unit. Place the black (–) probe on the ground connection of the sending unit
(Figure 11-39,
Page 11-38)
.
4. The following resistance readings in ohms should be obtained depending on the position of the float
inside the fuel tank. The resistance reading will vary according to the exact position of the float. The chart
below may be used as a guideline to determine if the fuel level sending unit is operating correctly. Make
sure the float is at the surface of the fuel in the tank.
FLOAT POSITION
RESISTANCE READING
FUEL GAUGE READINGS
Lower position (tank empty)
240 ± 20 ohms
Empty
Center position (tank half full)
120 ± 20 ohms
Half full
Upper position (tank full)
60 ± 20 ohms
Full
Figure 11-39 Fuel Level Sending Unit Test
TANK
CONNECTION
FRAME
CONNECTION
BLACK
WIRE
SENDING UNIT
2m
20
m
200
m
2k
200
200
200
200
20
2
200
m
500
20k
200k
2000
k
1000
OFF
WAVETEK
5XL
V
V
V
A
!
!
COM
200nA
MAX
1000 ---
750V
FUSED
2k OHM
SETTING