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Electrical Maintenance
92
5. If the output voltage is incorrect, check the
continuity of the wires that go from the J1
connector on the base controller to the sensor
as shown in the following table and make sure
the connections are clean and tight.
NOTE: The sensor cable wires are connected
to the sensor wires with solder connections
and heat shrink tubing during installation.
See the Precedent Single Temperature
Systems Installation Manual TK 55496 for
more information.
6. If the wires have good continuity and the
connections are clean and tight, replace the
sensor.
Important USFLS Replacement
Information
NOTE: This procedure covers replacing the
sensor. For information about installing the
USFLS Kit on a unit that does not already have
a USFLS, see the Precedent Single Temperature
Systems Installation Manual TK 55496 for more
information.
•
DO NOT
connect power to the UFLS until it
has been installed into the fuel tank.
•
DO NOT
use thread locking compounds as
they can cause stress cracking of the plastic
sensor.
•
DO NOT
apply any type of gasket sealer.
•
USE ONLY
new gaskets. Make sure to order
new gaskets when ordering the replacement
sensor.
•
DO NOT
use power tools to tighten the
mounting hardware or damage to the plastic
sensor will result.
•
DO NOT
overtighten the mounting hardware
or damage to the plastic sensor will result.
1. Remove and discard the sensor and the
gaskets. DO NOT reuse the gaskets.
2. Check the gasket between the sensor tube and
the tank to make sure it is in good condition.
Replace it if necessary.
3. Confirm the gasket surface areas on the tank
flange and the sensor tube are clean.
Pre-Assembly
The mounting holes of the sensor, sensor tube,
gaskets, and the fuel tank flange are not
symmetrical. The holes align only in one position.
The distance between the two mounting holes
next to the notch (see Figure 158) are further apart
than the others. These two holes will be used as a
reference point to correctly align the components.
J1 Con-
nector
Pin
Main/Unified
Harness Wire
Sensor
Cable
Wire
Sensor
Wire
1
8F-01
Green
Red
2
FUEL-01
White
Yellow
3
FUELN-01
Black
Black
1.
Sensor
2.
Pin Holes
3.
Mounting Hole Reference
4.
Notch
Figure 158: USFLS Components
2
1
3
2
4