9-5
9
Probe Troubleshooting
Minimum Detected Fluid Levels
13. Measure the resistance of the probe wiring from the probe end of the cable to its connections at the console.
First disconnect the cable from the console and twist the two ends together. Then remove the connector from
the probe canister. Measure the resistance across the two connector pins. The resistance should be low. It
should equal (approximately) the cable manufacturer's single conductor resistance per foot times the length
of the cable run times two:
-14 AWG should measure 2.52 ohms/1000 feet
-16 AWG should measure 4.02 ohms/1000 feet
-18 AWG should measure 6.39 ohms/1000 feet
If the resistance is higher than the cable manufacturer's specification, either the cable is defective or there are
poor connections between the console and the probe. If the resistance is within the cable manufacturer's spec-
ification, measure the resistance between one of the connector pins and the field wiring conduit to verify it is
not shorted (this resistance should be very high [megohms to infinity]). If the cable is good, reconnect the ca-
ble at the probe and the console.
14.Verify that the probe riser is not magnetized. This can be accomplished by using a metal paper clip on a string.
Dangle the paper clip suspended by a string into the probe riser to determine of the riser pipe is magnetized. If
the paper clip is attracted to one side of the riser pipe, replace the riser (this is rare, but it has occurred).
Minimum Detected Fluid Levels
Table 9-2. Mag Probe Minimum Detected Fluid Levels
Circuit
Code
Mag Probe
Type
Leak
Detect
Name
Plate
Color
Water
Detect
4” Ethanol-
Blended Gasoline
Floats
4” Floats
3” Floats
2” Floats
Min.
Fuel
Level
Min.
Water
Level
Min.
Fuel
Level
Min.
Water
Level
Min.
Fuel
Level
Min.
Water
Level
Min.
Fuel
Level
Min.
Water
Level
Mag Probes - Form Number 8473
C000
Std., 2 float
0.10 gph
Black
Yes
—
—
8”
0.75”
—
—
9.5”
0.75”
C001
Std., 2 float
0.20 gph
Red
Yes
—
—
8”
0.75”
—
—
9.5”
0.75”
D000
Std., Inv. only,
2 flt
None
Green
Yes
—
—
8”
0.75”
—
—
9.5”
0.75”
D001
Alt., 1 float
0.10 gph
Black
No
—
—
5”
—
—
—
7”
—
D002
Alt., 1 float
0.20 gph
Red
No
—
—
5”
—
—
—
7”
—
D003
Alt., Inv. only
None
Green
No
—
—
5”
—
—
—
7”
—
Mag Probes - Form Numbers 8463 & 8493
D004
2 float
0.10 gph
Black
Yes
7.000”
0.38”
3.04”
0.63”
3.04”
0.63”
3.23”
.867”
D005
2 float
0.20 gph
Red
Yes
7.000”
0.38”
3.04”
0.63”
3.04”
0.63”
3.23”
.867”
D006
Inv. only, 2 flt
None
Green
Yes
7.000”
0.38”
3.04”
0.63”
3.04”
0.63”
3.23”
.867”
D007
1 float
0.10 gph
Black
No
—
—
0.985”
—
0.985”
—
3”
—
D008
1 float
0.20 gph
Red
No
—
—
0.985”
—
0.985”
—
3”
—
D009
Inv. only, 1 flt
None
Green
No
—
—
0.985”
—
0.985”
—
3”
—
Mag Probes - Form Number 8468
